Many mean too well with their fruit trees and reach for mineral fertiliser as soon as the tree does not bear. Usually that is exactly the wrong move. An established fruit tree is a deep-rooter that fetches most of what it needs itself. What it really wants is fertiliser rarely, but a well-kept tree circle.
This article clears up the misconception that a lot of fertiliser means a lot of fruit. It shows you why the open tree circle and mulching matter more than any bag of feed, and how to help out gently with compost.
The tree circle matters more than the fertiliser
The tree circle is the area around the trunk, roughly as far as the crown reaches. Kept open and free of grass, the tree has no competition there for water and nutrients. Young trees in particular suffer badly when grass grows right up to the trunk.
So keep the tree circle open or mulched. That is the single most effective care measure, more effective than any feeding. Only on a well-kept tree circle does good compost really take effect.
Why too much nitrogen harms
Nitrogen drives growth. Too much of it, from mineral compound fertiliser or fresh manure, and the tree shoots into long, soft wood instead of forming fruiting wood. This soft wood is a magnet for aphids and more prone to diseases such as scab.
An over-fed tree thus grows a lot and bears little, the exact opposite of the aim. How diseases that follow overly lush growth connect is in Recognising fruit tree diseases.
How to supply correctly
- Keep the tree circle open
Keep the area under the crown free of grass, especially on young trees. That removes the strongest competition for water and nutrients.
- Feed with compost
A layer of ripe compost in spring on the tree circle is enough for most trees. It acts slowly and does not overload with nitrogen.
- Mulch instead of hoeing
A mulch layer of grass clippings, leaves or chippings holds moisture, suppresses grass and builds humus. Leave a ring free at the trunk itself so the bark stays dry.
- Sparing with nitrogen
Skip mineral compound fertiliser and fresh manure. If anything extra, then a dose of potassium, which supports fruit formation and frost hardiness.
Keep the tree circle open, help out sparingly with compost, avoid nitrogen. A fruit tree wants to be tended, not fattened.
The core rule for feeding
Frequently asked questions
How often must I feed a fruit tree?
Less often than most think. An established tree on good soil often manages without any feeding. If anything, a dose of ripe compost in spring is enough. More important than fertiliser is the open, mulched tree circle.
Which fertiliser is best for fruit trees?
Ripe compost. It acts slowly, does not overload with nitrogen and feeds the soil life at the same time. Mineral compound fertiliser and fresh manure, by contrast, drive soft, disease-prone wood.
Why does my tree bear much wood but little fruit?
Often too much nitrogen is behind it, from over-feeding or from grass and manure at the trunk. The tree then grows strongly but forms hardly any fruiting wood. Less nitrogen and an open tree circle reverse it.
Should I mulch the tree circle or hoe it clear?
Both are better than grass at the trunk. Mulching saves work, holds moisture and builds humus. Just leave a ring free right at the trunk so the bark is not permanently damp and rots.
When in the year do I feed?
In early spring, weeks 9 to 16, as the tree breaks bud. Later in the year you should give no more nitrogen, or the wood will not ripen before winter and will die back more easily in frost.
