Autumn is the best time to plant trees as this will allow time for your tree to establish its root system in preparation for next summer’s heat. Whenever a tree is uprooted, it loses most of its root hairs from which a tree absorbs much of its water and nutrients. These hairs will begin to regenerate upon planting, but it takes time. Transplant shock is a result of a tree’s water and nutrient absorbing capacity decreasing suddenly. To minimise transplant shock, it is important to regularly water your tree thoroughly, especially in the few weeks after planting.
Spacing should be based on a tree’s rootstock, which controls how large a tree ends up. This ensures there is adequate light levels and air flows, which prevents disease spread.
- Apples: M27, M26 and MM106 should be spaced 1.2m, 3m and 3.5-4m apart respectively.
- Plums: Pixy and VVA-1 should be spaced 3-3.5m apart and St. Julien A and Wavit 3.5-4.5m apart.
Planting In The Ground
Before planting your tree remove any plants in the circumference of your tree’s canopy as they will compete for nutrients and water. Dig a hole no more than an inch deeper than your rootball. With bare root trees ensure the graft point is above the ground.
Digging a hole with a larger circumference will allow you to improve the horizontal layers from which a tree gathers most of its nutrients. A mix of compost and soil will produce superior drainage/retention properties. Fertiliser will improve the soil’s nutrient profile and mycorrhizal fungi will ensure your tree can gather these nutrients.
A larger hole will allow you to plant a stake, which is essential for any tree with a M9/M26/M27/Pixy/VVA-1 rootstock as the roots are too brittle. The stake should be in pointing away from the prevailing wind, so as the tree will not rub against the stake, and no more than 2-3 inches away from the stem.
Water the root ball of your tree and free up any roots with your hands to ensure they aren’t growing in unnatural directions. Potted trees will sometimes have roots growing around the circumference of the pot.
With bare root soak the roots in a bucket of water. 30 minutes to 2 hours is common. Remember to not leave for too long as the tree needs oxygen too. Pruning woody roots back a few inches will stimulate the growth of more fibrous roots on which most root hairs reside.
Place the tree as so the graft is above ground level. Fill up any gaps with your potting mix, but do not compress the soil! Compaction will make it more difficult for water and air to reach your plant’s roots. The soil may reduce over time, so check up on your tree and add additional soil if necessary.
Give your tree a good watering and water bimonthly for the next two months. Adding mulch is recommended as it will improve the soil’s moisture retention. You can use bark and wood chipping, compost, manure, leaf-mould and stones, but be sure not to use infected materials. Make sure the mulch doesn’t touch the stem or it may transfer disease.
Tie your stake to the tree. Primrose recommends using a rubber tie that can be adjusted as your tree grows and nailed to the stake. Be sure to double knot your tie to prevent it from slipping. Placing a rabbit guard around the base of your tree is recommended as hungry rabbits nibble on bark come winter.
With bare root trees, cutting back the branches will produce a better balance between the root system and top growth, prevent the tree rocking in the wind and produce more fruit buds. Cut the central stem back by a third and the branches by half, snipping right above the buds.
Planting In Pots
With containers insufficient nutrient and moisture levels necessitates frequent watering in drought, biennial partial replacement of the soil and use of mulch. Using a potting mix of compost and garden soil will produce soil with the best drainage/moisture retention properties. Adding fertiliser is recommended to boost nutrient levels. When watering insure you give the pot a good drenching, this will ensure the roots grow to the extremities of the pot.
- Apples: 40-60 litre containers (35-40cm2 planters) is the minimum volume for a M27 tree. Choosing a tree with a M27/M26 rootstock is wise. M27 rootstock produces the smallest trees, but M26 copes best with underwatering. 140L containers are recommended for more vigorous rootstocks.
- Plums: success has been reported with both Pixy and St. Julien A, although it is recommended to use Pixy with smaller containers.
Adding fertiliser in spring will help your tree grow once it comes out of dormancy. Replacing any decomposed mulch is worthwhile. Check your ties to ensure there is no unnecessary rubbing. Come autumn, collect and compost fallen leaves to remove potential vectors of disease.
Pruning is key to establishing an excellent framework. Trees need to be bottom heavy with larger branches at the bottom than at the top. The central leader (main stem) should be higher than any scaffold branches (branches growing from the main stem) and competing branches should be removed. Scaffold branches will often grow vertically, but need to be weighed down when young, so they grow horizontally. Scaffold branches growing too close together are best removed. Keep horizontal branches growing off scaffold branches (secondary scaffolds), and remove vertical ones. Remove diseased, weak and twiggy growth and periodically thin to allow light to penetrate both the interior and lower portions of the tree.
Jorge works in the Primrose marketing team. He is an avid reader, although struggles to stick to one topic!
His ideal afternoon would involve a long walk, before settling down for scones.
Jorge is a journeyman gardener with experience in growing crops.