Growing Fruit Trees in Difficult Conditions
David Patch writes regularly for Kitchen Garden magazine and works at one of our main suppliers - fruit tree specialist RV Roger. We thought his piece on growing fruit trees in difficult situations was very helpful - so here it is as a guest blog - thanks for letting us borrow it, David!
“Well-drained but moisture retentive soil, sheltered position in full sun”. The Shangri-La of gardening. A mythical utopia where any plant will flourish. How many times have we read about a fruit tree that sounds great on paper, but then we find that phrase, guaranteed to strike dread into the 99% of gardeners who don’t have such ideal conditions to hand. Even if we do have the good fortune to have a favourable soil and aspect, much like the pool-side sun loungers at the hotel, the best spots have already been taken and we are left trying to spread out our towels in a cold, damp corner, exposed to the wind, or in deep shade.
At its heart, gardening is all about us imposing our will on nature. Mowing lawns, weeding, pruning and training - tasks which say that we are the ones in charge, masters of the universe. Even in the smallest of gardens we will have a range of plants from the four corners of the world, plants which would never grow side by side in the wild, but which we position together because it pleases the eye. Most gardening advice will also apply this egocentric view to growing in less than ideal conditions, proving advice on how to manipulate nature to allow us to do what we want. Improving heavy soils with organic matter, mulching dry sites and planting windbreaks are all excellent ways we can improve the hand we have been dealt, and broaden the range of plants we can grow. However the focus for this month is selecting the right plant in the first place - fruit trees and bushes naturally thrive in a wide range of soils and conditions, and if we can choose a plant which enjoys the conditions we have, the less we will need to intervene and the greater the chances of success.
Shade is the probably the most common problem for fruit growers. We all want to grow the best tasting fruit, and that generally means the sweetest- and it is direct sunlight which lets the plant form those crucial sugars. Any position where the plant gets less than 8 hours of full sun during the middle of summer is going to impact on the quality of the fruit. Instead, we need to turn our attention to the slightly acidic fruits, where this lack of sunlight will not be noticeable. Gooseberries, rhubarb, red and white currants will all do extremely well in almost total shade, and the fruit will be just as good as that grown in full sun. Indeed, gooseberries much prefer a heavier, damp spot, so if the soil doesn’t dry out they will not be as affected by the dreaded mildew which can spoil a whole crop. Rhubarb too will enjoy a damp shady position, and be much less inclined to ‘bolt’ and put its energy into producing a flower stem rather than the succulent young stems.
For top fruit trees which will take shade, again we need to look at varieties which produce naturally less sweet fruit. Cooking apples, culinary plums and damsons will all do well, and some such as the cooking apple ‘Lord Derby’ will happily set good crops in damp, cold spots with no direct sun. For dry shade, which is probably one of the trickiest sites, look no further than a morello cherry. Trained on a north wall, they will prosper and set excellent crops. Leave the fruit until the last possible moment for a depth of flavour which has to be tasted to be believed.
Wind is another issue, and one which can seriously harm a fruit tree and limit the crop. Cold spring winds can burn fragile blossom and foliage, as well as making it harder for pollinators to fly. The traditional advice is to plant a windbreak or shelter belt, but this is seldom a viable proposition for the home gardener. Instead, we need to be much more imaginative in ways to lessen the wind’s impact. Leaving neighbouring trees and shrubs unpruned can help, as can growing a hardy climber such as honeysuckle up a piece of trellis. It’s worth remembering that the goal is to filter the wind a little, not block it entirely. A complete windblock such as a solid fence or a row of evergreen conifers can actually be counter-productive, as the wind will funnel around or over them and cause more damage elsewhere. Select self-fertile varieties of top fruit, to reduce the journeys required by pollinating insects to get a good fruit set. Most plums and damsons will naturally withstand quite a lot of wind without impairing the crop.
Gardening in damp, heavy clay is a definite challenge. No fruit tree will do well in completely water-logged soil, as it deprives the roots of oxygen and encourages fungi and other pathogens which will attack the tree. If your soil is very wet, you really do need to consider options such as installing drainage or mound planting. However it is not all bad news - clay soils are extremely rich in minerals and conserve moisture better than thin sandy soils, so you should be less troubled by nutrient deficiencies or drought. Gooseberries, blackcurrants and raspberries will all appreciate a cool moist root run. Most apples will do well in a heavy soil, especially the scab-resistant varieties such as Ellison’s Orange, Sunset, Pitmaston Pineapple and Rosemary Russet, so are ideal in areas of high rainfall or on heavy soils. Quince trees will also tolerate wetter soils than most other top fruit.
At the other end of the scale are the thin, sandy or stoney soils. Here, regular mulching and feeding will be invaluable in retaining moisture and providing sufficient nutrients for plants to thrive. Strawberries will appreciate the good drainage, which makes them less prone to fungal diseases such as botrytis, but they will need a high Potash feed through the summer to produce the best crop. Both grapevines and figs will do very well in poor soils - they have extensive root systems which will search far and wide for food and water. Indeed, a thin soil will help stop them from putting all their energy into lush new growth, and concentrate on the matter in hand - providing delicious fruit.
For top fruit trees, the best advice is to go for a more vigorous rootstock than you think you need. Dwarfing stocks tend to be very shallow rooting, so can be badly affected by drought. Choosing a tree grafted into a semi-vigorous rootstock will mean the root systems are much deeper, tapping into water reserves far underground. Keeping the growth in check by regular pruning, rather than relying on a dwarfing rootstock, will give you a much happier, healthier and ultimately, more productive, tree.