There’s a lot to love about a cool season pip and stone fruit orchard – the stark and beautiful lines of naked branches, the rich reds and browns of resting bark, the deep blanket of leaf mould is the natural fertilizer of our fruit-bearing trees. However, don’t be tempted to spend too long admiring your orchard, or even your potted columnar apple or dwarf pear in its terracotta planter. The cool seasons may be a time of rest for your fruit trees, but if you want them to be productive and healthy, come spring, you need to put in the work while they are taking a break. And it starts with, nutrition.
Fallen leaves are certainly a help with fertilizing trees, but there is plenty more that can be added into the mix, and it needs to extend right out to the dripline (the outer reach of a tree’s branches). While commercial fertilizers can be applied in early spring, it’s not advisable to put them on the ground in autumn or winter (if a warm burst of weather stirs trees into life, the fertilizer will only promote growth which will then be cut back later in winter when cold weather returns).
However, what you can apply to the ground right now (again, right out to the dripline), are lashings of natural fertilizers which take time to break down, so won’t be available to your trees until spring. This can include lots of chopped kelp (or any other seaweed you can find), well-rotted animal manure, compost, chopped comfrey leaves, rotted lawn clippings, and more leaf mould.
It doesn’t matter how deep your layer of goodies is, as long as you keep it back from the trunk by about 20 centimetres (so you don’t ring bark your tree). While you’re at it, sprinkle a good handful of lime out to the dripline. This won’t become available to the tree until 12-18 months later, but do it each year when fertlizing, so you remember.
Lastly, cover your layers of organic fertilizer with something to stop the birds digging it up and scattering it in their search for worms. If you don’t mind looking at cardboard, open out cartons and hold them down over the your material with bricks or rocks. Alternatively, lay some weed mat or shelter cloth over the top, and peg it down with hoops of number 8 wire. (Avoid using bird netting, or your feathered friends might become tangled.)
Your next task is to treat your trees for fungal disease (unless you have heritage trees which are much less susceptible). Those who want to be purely organic should look to the likes of Biogrow for treatments such as ‘Free Flo Copper Fruit & Veggie’ and ‘Biosea Omega+Horticultural Oil’. Alternatively, head to the garden centre for orchard sprays of lime sulphur (this can’t be used on all varieties of fruit so check the label carefully). Lime sulphur controls both fungicide and overwintering pest insects, and is used at the end of winter for a thorough clean-up. Copper is a fungicide spray. It should be used at leaf fall, and again in late winter and early spring (it’s toxic to bees, so don’t use it when blossom is out).
If chemical sprays don’t appeal, it’s worth giving good old vinegar a go. The suggested rate is a tablespoon per litre of water, sprayed in late autumn, then monthly through June and July. Spraying of vinegar can continue through the fruiting season.
So many gardeners think simply popping a fruit tree into the ground, and staking it, is all that’s required to enjoy a harvest, but nothing could be further from the truth. Fruit trees are so worth having, but only if you are prepared to feed and care for them. It’s not much to ask in return for a basket of goodness come autumn!