Fruit Growers Treasure Trove

How to get fruit trees into production sooner

What to watch out for during the growing season

Unexpected tree death
Fruit set
Fruit drop

Pests and weeds

Pest and disease control
Natural predators
Grease bands
Chickens
Foxes
Pigeons
Apple canker
Peach leaf curl disease
Armillaria
Brown rot
Woolly aphid
Ivy
The goodies
Hedgehogs
Birds

When to harvest and how to store the fruit

Fruit picking
Storage tips
Ethylene filters
Pear ripening

Orchard hygiene

A good look once a week
Orchard hygiene for good crops
The effects of a Mediterranean climate on fruit trees
A fruity detective story
An old plum tree

How to get fruit trees into production sooner

Many people would understandably like their trees to start producing fruit as soon as possible. A tree left to its own devices tends to grow wood instead of fruit over the first four years. This is understandable: the tree wants to create a firm structure before hanging lots of heavy fruit on it! This gives us a clue as how to proceed. First, get the tree growing as soon as possible. Second, don’t prune the young shoots, in order to encourage the formation of fruit buds. Third, encourage auxin production by the root system. Let’s look at these in more detail.

We want the trees to achieve strong growth within months after planting, instead of years after planting. To promote strong growth early on, the tree should be planted in fresh soil, nutritionally well balanced and of a sandy loam nature with strong water-holding capabilities.

Interestingly, practical experience has shown that if trees are well supported, by a tall enough stake and/or interconnecting wires, the trees will crop significantly earlier. It’s as if the tree “senses” the degree of flexion of its branches and “decides” that the structure is strong enough to start fruiting.

To develop tree structure in its early years, pruning must be kept to an absolute minimum in years 1, 2 and 3 after planting. Tree formation is therefore carried out with the aid of stakes and wires instead of a secateur. By not cutting into the young shoots, the formation of strong fruit buds will follow. All we have to do is to tie the newly formed cropping wood into a near horizontal position onto the wires, during the month of August. Cropping will start the following year.

Obviously we have to aim to create the correct structure for the tree. This should be the form of a pyramid, in order to fully utilize the available light. Therefore at all times we have to maintain a leading central shoot, which initiates the pyramid structure. However, we can work on structure while the tree is cropping. This is the critical difference with respect to standard procedure. In the old days, one pruned during the first four years of the life of the trees, in order to manufacture a tree frame work. This stage was called the “tree formation stage”. Nowadays the emphasis is on early production and therefore minimal pruning.
Pruning is therefore necessary in order to secure a decent frame work, but it should be minimal. This pruning must never be carried out in spring at the start of the growing season. Carry out all your essential pruning when the fruit buds have already been formed. This is at the end of the growing season. The month of August and early September is ideal for this purpose. But not later!!

As mentioned above, the root systems of fruit trees will produce high levels of growth-promoting auxins, if the rooting environment, the soil, is conducive to this effect.

What to watch out for during the growing season

Unexpected tree death

Apart from old age, sometimes trees die unexpectedly, even at a young age.
The death of fruit trees can be caused by several factors:

1) Collar rot

2) Armillaria root rot

3) Soil contamination with aggressive chemical substances

4) Tree canker

5) Tree trunk restriction

6) Drought.

Drought is often the cause if the trees are not cared for and the competition of grass and weeds is too severe, combined with a long dry period. If this is not the case, then a careful examination of the tree will need to be carried out.

Examine the tree trunk very carefully. Is there an obstruction that has grown into the tree trunk and is causing severe restriction? If this is the case some new and healthy-looking young shoots will appear below the restriction. This will also be the case if tree canker is girdling the tree. Next, use a sharp knife to peel back a portion of the bark on the trunk. If no healthy yellowish cambium under the bark is present and the wood is brown and dead, then points 1, 2 or 3 , as mentioned above, are the most likely causes of the tree trouble. An example of Point 3 is when a chemical substance such as concentrated weedkiller has been poured onto the ground next to the tree.

If this is not the case, we will then be left with points 1 and 2 as the most likely cause. In both cases, the chance of the trouble spreading to other trees becomes an issue, because the fungus remains active on the tree roots. If it is the armillaria fungus, the toadstools will appear around the trunk in the late autumn period. However the bootlace-like fungal threads will then already have arrived around the roots of your nearest fruit tree or ornamental tree. In that case grubbing the tree in total is the only option.

Summarising, if after a detailed examination, you find that the likely cause of tree death is armillaria, then you will have to grub the tree immediately, remove it off the site, roots and all, and burn it, as soon as you can. Armillaria fungus is very active in finding and infecting its next victim.

Whatever the outcome of your examination, my advice is to always use new, clean soil if you want to replant a fruit tree. Taking into consideration crop rotation principles, do not plant apple after apple or pear after pear etc. Vary the tree types. So, for example, apple after pear will be fine.

Fruit set

Fruit set depends on the weather in the growing season. For example, a long, wet and cold spring can have a major influence on the year’s crop prospects. In these conditions, some trees may set reasonably well while other trees only show a light crop. Apart from the weather, trees that are free from grass and weed over an area of one square metre around the trunks of the trees, are able to set a much better crop on most varieties of fruit. For example, in late 2011-early 2012, many of us experienced the driest winter on record. Then it started to rain and it didn’t want to stop. The wind stayed in the North and it was very cold at the same time. As a result, when the trees were in blossom, there was very little insect activity in the orchard. The bumble bees were the only ones around. Pollination was largely achieved by wind-blown pollen. It is this sort of situation where orchard design, variety choice and micro climate will have a major impact on crop prospects.

Summarising, pollination, variety choice and soil management, and to a lesser extent the choice of rootstock, can still achieve a good crop of fruit, in spite of very unfavourable weather conditions during the blossom period. Therefore it pays to get the best advice applicable to your particular orchard site. Blossom periods are never alike. Some years the early varieties do best, other years the late flowering varieties excel. Therefore the best assurance of regular cropping of the orchard as a whole can be achieved by planting different types of fruit, as well as different and compatible varieties.

Fruit drop

Fruit drop is the process by means of which the tree decides how much energy it is going to dedicate to fruit and how much to growth. At the fruitlet stage, it eliminates a varying proportion of the fruitlets. We can then complete the process by manually thinning the groups of fruit so that the remaining fruitlets will be able to grow to a good size.

Some years, the natural fruit drop can be very intense: you may be surprised to see a carpet of fruitlets on the ground under the trees. Why does this happen?

For example, in 2013 weather in the UK was very different to normal particularly in spring. Usually a tree starts growing at the end of May, but in that year, the cold conditions and cold soil meant that the tree didn’t get the incentive to start growing until the second week of June. Then it realized (please forgive these verbs that seem to imply that trees have a human-like intelligence, but it’s easier to explain this way!) that it was late in its growing season (this information came from day length). So the tree started producing loads of new shoots.

New shoots need energy, just like the fruit which was also developing. This reduces the energy available for seed growth. When the seeds do not develop properly, the tree abandons the fruit around it, and it drops.

Different varieties have different thinning characteristics. James Grieve has a perfect, automatic thinning. No manual thinning is required. This year, Early Windsor ignored all the seasonal information as described above, and set a heavy crop.

Pests and weeds

Pest and disease control

When you plant a few fruit trees, you are offering an invitation to hundreds of different forms of life. A tree is not a species living in isolation from the rest of nature. It immediately generates a unique habitat both above and below the ground.

Some of the birds, animals, insects, fungi, lichens and plants that interact with the tree are beneficial. Some are neutral. Others are harmful. Managing the biological equilibrium of a single fruit tree, a garden or a small orchard is a difficult but fascinating task. Today, tree experts can reduce the use of chemicals to a minimum, and with careful management, trees can be kept healthy even in a totally organic pest control programme.

The fundamental concept in organic pest control is exploiting the fact that in nature, friend and foe live together in the same environment. Rather than to attempt to chemically eradicate pests, the organic method is to provide their predators with a happy home, in other words ensuring that the type of plants necessary for successful breeding are present.

Natural predators

ladybird
Photo by Vincent van Zalinge on Unsplash

One of the most damaging group of insects comprises, for example, the various types of aphids. There is no need to resort to repeated annual chemical control measures as long as the various predators of the aphids are living stably and comfortably in the orchard as well. These predators include lacewings, hoverflies and ladybirds. Provided there are enough of them in the orchard environment, the aphid population will never be so great as to cause serious damage to the fruit tree foliage and the fruit itself. So the point is to build up the predator level in order to keep, for example aphids numbers down.

 

 

This can be done in various ways:
– providing homes for predators, such as lady bird boxes and lacewing hotels;
– making space for a couple of beds of well-grown companion plants such as chives, pot marigold and alpine strawberries;
– placing nest boxes at the right height in the trees for the various tits. Make sure that the entrance is woodpecker-proof and cat proof;
– putting grease bands on the tree trunks from October to May;
– removing any bypasses such as tree suckers and/or tall weeds (for winter moth control).
– taking orchard hygiene seriously, in order to keep the number of trees infected by various diseases at as low a level as possible.

This last point is of the greatest importance. If during the growing season, fruit and leaves were seriously infected with various pests, such as codling moth, sawfly, or diseases such as scab and mildew, then the early removal of these fruits and leaves after they have fallen on the orchard floor in late autumn is the most effective way to reduce infection levels at the start of the next growing season and to bring balance back in the orchard environment.

Grease bands

Grease band
Grease band, photo courtesy of the Royal Horticultural Society

If you would like to reduce the harmful effect of caterpillars in the early spring, munching away on the newly-appearing blossoms and young fruitlets, without applying chemicals and insecticides, then grease bands are an old-fashioned but highly effective method. They are based on the principle that the females of various insect species are wingless and begin to crawl their way up the tree, via the trunk or low-hanging branches that brush the ground. The stake next to the tree may be used as a route to climb into the tree. The pests I am referring to are the larvae of the Winter Moth, the Mottled Umber Moth and the Vapourer Moth. These larvae, once they have arrived at their destination, will begin to deposit their eggs around the fruit buds and in the crevices of the bark all over the tree. No damage occurs this time of the year. When the winter has passed and the temperatures begin to increase, then the eggs of the larvae will produce lots and lots of little caterpillars. These will begin their munching feast on all that freshly-appearing green foliage. Then, worse still, once blossom time is over, they will then start chomping away at the young fruitlets just as they are appearing.

It is in early-mid October that the larvae of those insects begin their journey from the soil into the trees. If applied correctly, the grease bands will trap them. Follow the instructions on the packet. Any good garden centre stocks them at this time of the year. Keep your grease bands in place through to the end of April as in the spring other insects will also try to climb into the tree for the same purpose. Grease bands are therefore very valuable not only at this time of the year but also during warm days in the winter and the spring, repelling all sorts of creepy crawlers. Remember to attach them to the stake as well.

To tell the truth, I have only ever used grease bands of the type in which the sticky stuff is on sheets of plastic, so that the grease itself is not in contact with the trunk. There are types of grease sold in tubs that can be applied direct to the trunk of your fruit trees, as shown in the photo. Perhaps someone could tell me about their experience on this. In any case, another thing that should be done at this time for the same reason is to cut the low ground-touching branches back to at least 18 inches above soil level.

 

Chickens

Now, if you have a nice little orchard with wire netting around it, keeping the chickens in, then most of these wingless insects will have been consumed by the chickens. There is no better way of biological control of various pests, than having lovely egg-laying chickens settled in your orchard. What’s more it is a wonderful way of not only daily collecting the chicken eggs, but also at the same time keeping an eye on your beautiful fruit trees.

chicken amongst fruit trees

Foxes

Foxes sometimes raid the apples on trees. How can you prevent this from happening? When the fruit is beginning to ripen, it is often effective to hang a small, highly scented piece of soap using a metal S-hook. This often deters foxes and deer. Once the piece of soap loses its scent, it is no longer effective. Check and replace it if this is the case.

Pigeons

Pigeons can cause damage particularly in April, the time of the year, when the first newly emerging little leaves are a great attraction in all areas where pigeons are present in great numbers, where field rape is grown. The pigeons show a great desire to vary their food source. After having grazed the rape fields, the pigeons will move for a while to the nearest hedge cover. From that point they will attack any type of plum or greengage, severely damaging any blossom or young green leaves.

The net result is that the crop prospects of those trees will be set back greatly and may result in no crop at all. Anything that can be done to scare the pigeons away is worth trying. A mixture of various deterrents is better than just one.

The length of the period during which the trees are at risk will greatly depend on temperatures and type of weather. A long cold spell in early spring is the most damaging situation in terms of pigeon damage, because of the shortage of fresh green growth.

How to protect against pigeon damage

Without blossom, there can be no fruit set, and so no fruit! Therefore if damage is only slight, no action needs to be taken. If the cold period continues, pigeons are capable of literally stripping off all the blossom. Black cotton threads, woven through the flowering branches, will usually stop the damage. Just wind it around the tree (slip the spool onto a rod or dowel to make things simpler) so that the threads are about six inches apart. What happens is that the bird flies towards the tree, doesn’t see the thread, touches it with its wing, gets a fright, and flies off. No damage to the bird is done, and it helps save the blossom!

Apple canker

CankerThis a serious disease which needs to be identified, and, if present, it has to be eliminated from young trees. The roots of the trees are not affected. Canker is a fungal infection, and it used to be treated with copper-based sprays. These have been withdrawn from the market, under EU regulations. Therefore the only means to eradicate this fungus is to cut out all diseased wood. It must be removed from the orchard and burned. Spores continue to be released from wood on the orchard floor, particularly during the dormant period of the fruit trees. That’s why as a matter of urgency, all cankers on the tree trunks, whether large or small infections, have to be exposed, by removing the tree guards, and then cut out. The wound should be painted with “heal and seal,” with at least a 1-inch overlap, right around the trunk if necessary. This method of control has to be completed by no later than the end of October. A second check of the treated wounds should be carried by the end of March, before the trees get into leaf.

If you find a lot of canker infection, it may be necessary to adjust the nutritional programme of the trees. Nitrogen and high humidity make the ideal conditions for rapid growth of the canker fungus. Therefore, if your trees are suffering from canker, it is wrong to apply any nitrogen from September to the end of February. If nitrogen has to be applied, it is best to do it during the first week of March.

Peach leaf curl disease

Peach leaf curl
Peach leaf curl, photo courtesy of Scot Nelson/flickr.com

Did your peach, nectarine or apricot look odd with reddened, screwed up, puckered leaves?. Or no crop or very little? That’s most likely the result of the fungal disease “peach leaf curl” and frost damage. It can be avoided by covering your peach tree or your apricot tree with a double layer of garden fleece from late January until the middle of May, every year.
Peach leaf curl disease is caused by a fungus, Taphrina deformans. It will attack the tree species of peach, nectarine and apricot. The symptoms are the development of large reddish blisters on the leaves. The tree is weakened as photosynthesis by the leaves is seriously affected. Eventually the tree is starved to death as it is no longer able to make the carbohydrates it need, through photosynthesis. Leaves tend to fall prematurely and growth comes to a complete standstill.
The fungus attacks the tree from late January until the middle of May. After May the fungus is no longer producing spores and therefore cannot cause new infections.

How to avoid these troubles

There are various options for controlling this fungus. Some varieties are more resistant than others. However this is no help if you already have to cope with this problem.

Actions to be taken immediately are the complete removal of leaves affected. This applies to all the fallen leaves as well as the affected leaves still attached to the tree. In late October/early November, make sure the leaves are all collected up, infected or not, put in a plastic bag and then put in the non-recycling bin. The fungal spores survive over winter on the fallen leaves!

Once the soil underneath those trees is clear of all litter, cover the soil with a 4 cm-deep layer of straw-based farm yard manure. Leave no gaps uncovered. The area to be mulched must be of a minimum size of one square yard.

Make sure the tree is well watered and does not stand in a carpet of weeds and grass. Apply a full watering can of water twice a week, particularly during the summer months.

frame for fleecePhase 2 is equally important; it has to do with making sure that the “Peach leaf curl” fungus no longer has a chance to disfigure your tree. Make yourself a framework, as illustrated in the photo, to stop the new young foliage becoming wet. Cover the wood frame with plastic or garden fleece. The framework is needed to stop the plastic or garden fleece cover, touching anywhere any limb or branch or twig of the tree. By keeping the young newly-emerging foliage dry, the spores of the fungus are unable to germinate on the newly emerging foliage. Don’t forget that these trees flower very early in the season. The new cover will also protect the blossom from damaging spring frosts. And finally when the fruits are nearly ready, the wooden frame is also very useful to fasten on to some netting, to stop the birds eating your peaches or apricots, before you had a chance to taste the fruits. Make sure the wind cannot affect the fleece or lift it off. Keep your eye on the tree and if a tear develops in the fleece after particularly bad weather, repair the damage properly. This fleece needs to stay in position until the second week of May. After that time, carefully remove the fleece.

Never prune the tree during the autumn and winter months when the leaves have fallen. It is at that time that new infections occur very quickly. Prune during the middle of May or during late August, making sure that the old wood is removed to make room for new shoots to form. This is essential as the fruits of peach and nectarine are formed on one year wood only. Seal the pruning cuts with “Prune and Seal”, a compound available from your garden centre. The foliage of a well pruned tree dries up quickly, with less chance of new infections.

If it is not possible to cover the peach tree, to avoid the disease you can spray with copper during the first week of February and repeat the spray 14 days later. Follow the instructions on the packet in detail. Garden centres stock it. At leaf fall in late November put on another spray of copper.

Peach leaf curl disease is spread by rain droplets. The fungus over-winters and is hidden in crevices of the bark and between the bud scales. Therefore consider planting a peach tree in a 15 to 18 inch diameter pot. By the end of January, wheel the potted peach tree into a cold shed or a cold green house or a cold poly tunnel. In that way no fleece is needed as the tree is sheltered from the winter rains. By the middle of May it is safe to take the pot outdoors again. Then position the tree in a warm sunny place and water it weekly or twice a week when very warm weather is occurring. Never let the tree go short of water as it will surely die.

Feed the tree monthly with a suitable foliar feed, obtainable from garden centres.

Armillaria

armillaria illustrationThe illustration is from “The Book of gardening: a handbook of horticulture”, 1900, edited by William D. Drury. It is accompanied by the following text:
Armillaria mellea (Agaricus aielleus). This is a most destructive fungus found upon living ornamental trees, such as Conifers, as well as upon orchard trees. It is responsible for the disease known as Tree Root Rot. The fungus is most abundant, and is found both as a saprophyte and as a parasite. The clusters of Mushrooms at the base of trees are very familiar; they are, moreover, conspicuous alike as to size and colouring. The cap is of a pale yellow, with darkish scales upon it; the stem is also yellow. The fungus finds access to healthy trees either by means of its spores, which germinate on an injured part of the bark; or by means of the very peculiar mycelium, which is black and string-like, and always endeavouring to penetrate the roots of healthy trees. The only thing that can be said in favour of this fungus is that its sporophores, or Mushrooms, are edible, though not particularly rich in flavour, being somewhat strong. Care should be taken to carefully remove and either eat or burn all specimens of the fungus, so that the danger of trees being infested by the spores which are shed is minimised. The mycelium found under the bark is white and felted. Once a tree has been badly attacked nothing can save it from destruction, as the mycelium spreads under the bark with considerable rapidity. Preventive rather than remedial measures should be adopted. These may well consist in the removal of all dead stumps on which the fungus is growing as a saprophyte; and in isolating the infected live trees.”

Armillaria honey fungus
Armillaria honey fungus, photo courtesy of J. Maughn/flickr.com

Brown rot

Brown rot
Brown rot, courtesy of Barockschloss/flickr.com

If there is one fungus which is a real trouble when fruit is ripening, as well as during blossom time, it is this brown rot fungus. It is caused by three different fungi: Monilinia fructigena, Monilinia laxa and Sclerotinia fructigena. It also infects blossoms of fruit trees, which become brown in appearance; the problem may persist in the trees well into early summer. It is when the fruits are beginning to ripen, whether they be apple, pear, plum, cherry, peach, nectarine or apricot, that the brown rot fungus becomes really active. The conidia spores enter the fruit through small wounds or bird pecks, and germinate. The destructive spores soon develop and the fungus spreads around growing fruit. If the weather is favourable it is able to destroy a very significant proportion of the fruit crop. Warm and humid days suit the fungus best. It may even affect the thin young shoots, which have been supporting the growing fruits.

 

Woolly aphid

Effective insecticides for woolly aphid are no longer available to the gardener or the allotment holder. Using luke-warm water and some detergent, brushing the affected branches will reduce the problem. Repeat the same treatment a month later.

Woolly aphid

Ivy

Ivy is a good source of winter feed for birds in relation to its flowering at that time of the year. However ivy must not spread out along the branches of its host tree. Ivy then reduces the light quality too much and the host tree will suffer. Ivy climbing up the trunk of trees does no harm at all and is therefore a valuable part of the ecosystem.

Ivy just uses the tree as a support. It roots just cling on to the bark, they don’t extract any nutrients from it. So if you have some mature trees with ivy, you just need to cut back the ivy from where they are growing into the branches.

The goodies in your garden

In spring and early summer, do make time to visit your trees and see if all is well with them. There are baddies around which will be harming your trees especially when conditions are warm. Look after the real friends of your fruit trees which are trying to do their best to produce crops you will enjoy.

The goodies - earwig, lacewing, ladybird
The goodies – earwig, lacewing, ladybird

 

In the warmer months of the year there are many visitors in and around your fruit trees. Some are good, others are harmful. The fruit tree defenders, to keep the baddies in check, are the ladybirds, the earwigs and the lacewings. These friends will do their best to stop greenfly of all sorts from gaining the upper hand and ruining the leaf surface. Damage to leaves makes it more difficult for trees to make their various foods. Encourage the lacewings, ladybirds and earwigs by providing them with homes to live in and do not kill them off with harsh chemical sprays. There are plenty of sprays which can be used in the gardens and small orchards, based on organic principles, which will do this job very well.

Ladybird hotel

Talking about providing homes for beneficial insects and various other living creatures, do spare a thought to the small birds in and around your garden. These have insect-based diets and get rid of many aphids and caterpillars. The large family of blue tits and long tail tits are good examples. Make sure you have nest boxes at the right places for them to make their homes in your garden. One final point: when your fruit trees are in blossom, do not spray them with anything. Wait until the blossom is over. That’s the time to visit your trees weekly and monitor what is going on. If the leaves are curling or showing signs of drought, be ready to water your trees and take action. If too many aphids are curling up the leaves and therefore harming your trees drastically, reduce their numbers.

Hedgehogs

If you have trouble in your garden with slugs and snails, make your garden desirable to hedgehogs; your slugs and snails problems will magically disappear! But how do you make your garden desirable to hedgehogs?

Hedgehogs by nature do move around a lot. Therefore if the garden is fenced in, do make sure there is a wide enough gap at soil level, roughly the size of a football, to allow the hedgehog to travel. Secondly a hedgehog needs rough corners or patches in the garden where it can hide. They love a mixture of semi-wooden plant material, dry grass, which can also provide warmth during the winter months. Here in the UK there is a hedgehog club, which actually sells hide-outs or will provide drawings showing how to make one yourself. Hedgehogs love snails and slugs, that’s their staple diet. So never spread around slug pellets as it will kill them or make them seriously ill. If you like to feed them, use cat food but NEVER milk on a saucer. An ultra-tidy garden does not offer anything of interest to hedgehogs.

Birds

During the winter months, gardens are the most important places for birds to find that extra bit of food to keep them alive and well and get them through cold, damp and frosty periods. Bird tables don’t take a lot of effort to make, either by yourself or your partner. It is amazing how much we can learn from the behaviour of all these birds, they have their own likes and dislikes. Once spring arrives then these little birds repay us by clearing up all sort of niggly problems such as aphids and caterpillars which feed on the trees that we have just planted or are nearly ready to harvest.

Bird table
Bird table, photo courtesy of Tamsin Cooper/flickr.com

When to harvest and how to store the fruit

Fruit picking

Only pick your fruits when the weather is dry. The net effect will be that the fruits keep better when stored in the cool for keeping. For immediate consumption or juicing, pick the fruit when the taste is to your liking, irrespective of weather conditions.

Pick apples which taste right, before they are fully mature. Store in a cool vermin-proof, dark place. Spread out in a single layer. Any sound but slightly damaged fruit needs to be eaten or juiced now. Only sound fruit should be stored for the longer term. Do not try to store fruit which is damaged, as it soon will start to rot.

Some cooking and eating apples are of such good storage quality that you can keep them in good condition until the next lot of apples are ready next year! The ideal temperature is approximately 3 degrees Celsius. The bottom of the fridge is about that temperature.

How do you know when apples are ready to pick?

Many people wonder how to be sure to pick the fruit at the correct time. If picked too early the fruit will shrivel and will be lacking in flavour. If picked too late, fruit will have started dropping off the tree, because over-ripeness is often the main cause of the drop. November is the time to pick the last varieties of apples that are still hanging on the trees. The last apples to be picked usually have the best storage life.

The best way to judge if the fruit is ready to harvest is to lift the fruit gently. If the stalk gives way and therefore easily parts from its base on the branch, then this is the first indication that harvest time has arrived. The second test is to taste the fruit. If the flavour is fully developed and the fruit is very juicy, while still nice and crisp, then you are really sure the fruit is ready to be picked.

Storage tips

Apples are the easiest fruit to store. Pears can be stored successfully but only if you are able to keep the temperature as close as you can to 1 degree Celsius. Apples store well at 3 degrees Celsius. Plums, greengages, peaches and apricots are best ripened off in the kitchen and used for daily consumption or bottling.

Tips on storing apples

In autumn, remember the following if you want to store some apples for the winter months:

1) Pick fruit for storage when it is cool, so early in the morning.

2) Only store fruits without holes, cracks or small patches of discoloured brown rot.

3) Pick very carefully. Handle the fruits like eggs. Bruising the fruit is as bad as a hole in the fruit.

4) Do not store over-mature fruit. These fruits won’t keep. Store fruit that is slightly under-ripe to maintain fruit firmness.

5) Colourless immature fruit from the centre of the tree tends to shrivel once in store.

6) The taste of the fruit must be fully developed, before it is ready to pick. Always taste the fruit first, before you pick it.

7) Put the fruit on single-layer trays.

8) Keep the temperature ideally at an even level and as close as you can to 3 degrees Celsius.

9) Fruit stores best in the dark and at high humidity.

10) Make sure mice are not present where you store your fruit as they will nibble the fruit and destroy your harvest.

11) Remove fruit showing signs of rot.

12) Inspect your fruit once a week and remove those fruits which ripen first and are ready to eat.

Fruit storage and ethylene filters

I tested an ethylene filter designed specifically for smaller-scale fruit growers over a 12-month period. When fruit is put into store, it is alive, and so it carries on its metabolism though at a slower rate due to the cool temperature. Apples and pears produce ethylene as they ripen, and this changes the fruit colour and gradually makes it softer. So an ethylene filter, such as that by Fresh Pod, tested in the trial, helps fruit in store keep better and for longer, without losing flavour or firmness.

The ripening process of pears

PearsWhen one goes to the supermarket and buys some pears, usually the pears are still firm and even hard depending on the variety. What is not generally known is that a lot has been done already, before these pears were offered for sale, to make sure that the pears will ripen properly when taken home. To start off with, there are many different pear varieties. Basically there are some pear varieties which have to be picked earlier than others. Take, for example, Williams pears or Beth pears: by nature these are the earliest to mature. Now these pears will have to be picked when they are not fully mature. If they are left to ripen on the trees, usually the juiciness and flavour is disappointing. Then there are late maturing pears which in this country fail to mature on the trees. So, in order not to complicate the issue further, what is the best practice for someone who has a couple of pear trees and a good crop, and would like to have the pleasure of eating a wonderful juicy pear, grown in their own garden? In addition, for pears grown in a garden, it’s nice to be able to spread their maturing out, as it would be impossible to eat them all in one go.

The answer to these questions may come as a surprise. First, you can control pear ripening by picking them when they are still hard and then keeping them in the fridge. Keeping them in the refrigerator for a few days actually improves their ripening when you take them out.

So this is the process: pick the pears when they are ready but still hard. How do you know when to start picking? Assuming you have watered your trees weekly and good fruit size has been achieved, then the following test is useful; lift the pear gently and when it comes away naturally, the stalk breaking easily, then the optimum picking time has been reached. When picking, do make sure that the pears are handled like eggs. Any bruising translates into early rotting. Then put the pears into the bottom of the fridge without delay. Keeping them in the dark for several days at a temperature close to 1 degree Celsius ensures even fruit ripening later on. From then on, you can take two or three pears out of the fridge and leave the others in the fridge. The ones left in the fridge stay hard, while the ones put in the fruit bowl in the living room will start to soften quite quickly. Feel the fruit near the stalk end and press gently to see how soft it is. If it has softened at that particular spot, the pear is ready to eat.

Orchard hygiene

Its effect on quality of fruit and general tree health

A lot of the diseases that can afflict fruit trees are caused by fungal spores that infect the tree through even a small wound. It is possible to reduce the chance of infection by simple operations of orchard hygiene that make it possible to grow quality fruit without the use of chemical pesticides and fungicides. The basic principles are: eliminate the sources of fungal spores; and seal any open wounds on the tree.

Once you have picked the fruit and removed non-productive branches from the tree canopy, remove all the fruit left on the ground and eliminate it – in other words, not on the compost heap! It has to go into the non-recycling bin. This helps reduce the number of spores floating around your trees. Remove any branches affected by mildew. They’re easy to spot, because they have a silvery appearance. If irregular brown growths are appearing on some of the branches, these should also be cut out. The same goes for wood infections such as tree canker or bacterial canker. Take a look at the tree ties on the trunk and branches to ensure that they haven’t become so tight that they’re ingrowing. After all this, cover any wounds with a sealing compound such as “Heal and Seal” using a smallish paint brush.

In winter, there will be more orchard hygiene work, but we’ll get to that in due course!

A good look once a week

Aphis life cycle
The life stages of the green apple aphid (Aphis pomi). Drawing by Robert Evans Snodgrass, 1930

A good look at your fruit trees once a week is all its take for your fruit trees to do well.

Trees can look after themselves reasonably well once they have been in the ground for a year or two. It is the first 2 to 3 years when the trees need a helping hand from time to time. This has all to do with the fact that trees, like everything else that grows in your garden, will need to adjust to the prevailing conditions. By that I mean it will take time for the various predators to settle either in or close by your trees to keep the various pests under control. For that reason young trees often suffer from aphid attack in spring. As soon as you notice that some leaves are beginning to curl, open the leaves up. If aphids are present then you have to deal with this. You can try to remove them with water or organic soap. Or your garden centre will have a wide variety of liquids, organic or otherwise to deal with this problem. You can also try to cut the affected leaves off and put them in the non-recycling bin.

In my experience, orchard hygiene and companion planting are the two most important factors in keeping pest and disease pretty well under control, without having to resort to sprays and various chemicals. Patio trees are often found to be in very good condition. The simple reason is that as a matter of routine any diseased or distorted leaves have been regularly removed during the growing season, from the patio.

Therefore it is a very good habit not to let things drop on the ground or anywhere near the trees, but to put diseased twigs or leaves in the non-recycling bin. In that way one avoids a build-up of various afflictions.

Fruit that has dropped, or rotting fruit, must not be left under the trees.

If your trees are in the chicken run then things become easier still, as the chickens are fond not only of the dropped fruit but also remove lots of grubs and caterpillars which otherwise would have had a go at the ripening fruit.

Many of the scab and mildew spores overwinter on fallen autumn leaves and twigs. To avoid re-infection in the following spring, it pays to remove and dispose of the old leaves by the end of November/ December. From that point of view it is a good move to tie grease bands around the trunks of the trees. Most garden centres stock them. It will stop various insects such as the winter moth from crawling up the trunk of the trees and causing damage to foliage and young fruitlets.

As mentioned earlier, over the medium term it is an excellent idea to build up the numbers of predators of the various pests which may harm the fruit and the leaves. Each predator has its own specific host plant, tree or bush. If you have the room to grow these various plants, then the various pests will be kept under control by natural means.

Hover flies, lacewings and ladybirds are all very active in keeping various pests such as aphids and red spider mite at a low level. Nasturtiums, marigolds and fennel attract hover flies into the garden. Earwigs consume many young aphids in various stages of development. They like to overwinter in upturned flower pots filled with straw or short cut bundles of open bamboo canes.

Provided one is in the routine of feeding small birds such as blue tits and long tail tits during the winter months, these little birds consume lots of grubs and caterpillars which otherwise would have found their way into the fruits. Finally, garlic sprays are abhorrent to many insects. These can be obtained from most garden centres, in case the predator numbers in a particular season are at a low level.

Good crops of fruit and orchard hygiene go together

A very good gardening friend of mine, who lives in one of the surrounding villages, has demonstrated in practice, year after year, how it is possible to grow all types of fruit without the intensive use of manufactured chemicals, irrespective of variety, pests or diseases, or bad weather conditions, such as low temperatures at blossom time. He takes great care to ensure that his trees grow in an environment in which the chances of infection have been reduced to a minimum, by practicing the elementary principles of good orchard hygiene.

Once he has picked the fruit and removed non-productive branches from the tree canopy, he makes a special job of removing any fruit left on the ground underneath the tree crown. He picks up all deteriorating fruit, however bruised or rotten it may be, and puts it all in the non-recycling bin. The net effect of this action is that there are less spores floating around his fruit trees next year, and so there is less chance of fungi finding a spot to infect his fruit. Another benefit of this is that his fruit is of better keeping quality. In addition, he removes any wood affected by mildew. This is easy to spot as it has a silvery appearance. If brown irregular growths are appearing on some of the branches, he makes sure it is cut out in early October. Likewise, he cuts out wood infections such as tree canker or bacterial canker, and he ensures that any ingrowing tree ties on the branches are removed. The wounds are then covered with a sealing compound such as “Heal and Seal” using a smallish paint brush. This is very effective and stops new infection occurring this or next season..

During the winter months he will further attend to his trees and remove lichen and tree moss which are reducing the young branches’ ability to produce good strong fruit buds.

The effects of a Mediterranean climate on fruit trees

The new weather patterns caused by global warming are causing, in many areas of the UK, above average rainfall and higher than average temperatures. Winter months may be virtually without frost and therefore the season starts earlier. Most types of fruit ripen earlier than usual as a result of these weather patterns.

There are some negative effects as well. There is a lot more brown rot to cope with. Also various fungal diseases such as scab and mildew have caused problems for many people. Orchard hygiene is therefore very important. Removal of rots and scabby leaves from the orchard area is very important. If this is not done then next year the problem is likely to be even worse. This also applies to peach leaf curl. Do not store any affected fruit. Only store clean undamaged fruit.

A fruity detective story

The story begins with a letter.

“Hello Dan. Three years ago I bought 2 plum trees (1 Czar and 1 Marjories Seedling) and 1 apple tree (Bountiful) and now they have grown into sturdy trees. The Czar and Bountiful produced prolifically last year and the Marjorie Seedling less so, but this year it appeared that all three would produce magnificent crops (despite the best efforts of wood pigeons to strip the plum trees of their leaves). However, two weeks ago or so I noticed some brown patches on my Czar plums which have further developed and spread, and I am 99% certain that the tree is suffering from brown rot. Worse I am pretty certain that it has also spread to the other two trees, although it is in a less advanced state.

“I have removed the fruit concerned and I have sought information on the internet for a cure. However, all the advice is that, because this is a fungus, no cure is available. I understand that I may have to accept that I will lose this year’s crop and my main concern now is how to prevent a recurrence of the problem next year, if indeed prevention is possible. Any advice you have on what I can do in this respect would be greatly appreciated. Thank you for any help you can provide. Yours sincerely, B.G.”

This is what I wrote back:

“Hello B. Usually brown rot only occurs on fruit which is nearly ripe to eat. I am therefore not at all sure it is indeed brown rot. In order to be more positive, please send me some pictures attached to your next email. I will need a picture of the tree as a whole, a close up picture of the leaves and another picture of the worst affected fruits on the tree.”

Here are the photos of the Bountiful apple tree that Mr. B.G. provided:

apple tree and brown rot

apple hail damage and brown rot

And here are the photos of the Marjorie’s Seedling plum:

Marjorie's Seedling hail damage Marjorie's Seedling leaves

The photos clarified the situation, and I was able to write back to Mr. B.G. immediately.

“Thank you for the pictures. Yes I do know what has happened. But first the good news!

There is nothing wrong currently with your tree; good dark green foliage and good sized leaf.

The bad news is the fruit which has been totally destroyed. The cause is the spores of the fungus ‘Brown Rot’. Earlier in the season you must have had a hailstorm. The pit marks on the fruit are visible on your photos. Wounds in plum fruits do not heal. Brown Rot fungus spores are in the air, throughout the growing season. After the hail the fruit got infected with these spores and I am afraid destroyed your crop. The points you should consider are the following;

1) Look out for a stump or old plum tree in your area, which could be the source of infection. Destroy that tree.

2) Thin your fruit to 2 per cluster as a standard procedure by the middle of June in any year. Space these doubles 6 inches apart. Brown rot fungus thrives in clusters of fruit.

3) If hail occurs again next year, spray without delay with Systhane fungicide. Once the spores get in the wounds it is too late. You can purchase Systhane from Amazon for little money!

4) Do remove all affected fruits as soon as possible from your garden. The fungus will overwinter on the fallen fruits and be ready to infect next year’s crop.

5) Water the soil under your tree during dry hot periods. If the soil dries out and then rain follows, the fruit will split and as a result, create many points of entry for brown rot spores.

6) Spray your fruit trees before leaf fall in November with Bordeaux mixture. This will safeguard the tree against silver leaf and bacterial canker infections.”

So, all clear. The hunt is on for the rotting plum tree stump that caused it all!

An old plum tree

A reader writes: “We moved house in August last year, a beautiful garden with a plum tree which gave us lots of plums. It’s very old I think! I’m wondering how to prune, some of the branches are just snapping off! I need to ruin it I think! Can you help and give me some advice?”

Here is the advice we provided:

Old plum trees very easily fall prey to two specific diseases: Bacterial Canker, and Silver Leaf.
Therefore, special attention needs to be given to the following points:

1) only carry out pruning operations when the tree is in FULL LEAF stage;

2) reduce the weight of the total number of branches. Remove those which are old and broken and leave the well-illuminated branches;

3) remove the too-dominant near-vertical branches;

4) always immediately seal the wounds with Arbrex, obtainable from garden centres;

5) do not let the tree cope with droughty conditions during the summer months – ensure it gets enough water;

6) do not over-crop the tree. Thin the fruitlets during June and July.

thinned damson
Damson after thinning