Fertilisers are concentrated sources of plant nutrients. They feed plants rather than feeding the soil. Fruit trees benefit from regular fertiliser. There are many types of fertiliser available, all with different nutrient values.
- Make sure that the soil is moist – late winter or early spring is best
- Sprinkle the fertiliser over the tree's rooting area (that is the area just beyond the branch canopy). Moderate the quantities given if the trees are growing vigorously
Three main elements are need for plant growth: nitrogen (N) to encourage good growth, phosphorus (P) for root growth and potassium (K) for fruit and flowers.
Apples need nitrogen fertiliser annually, with culinary apples requiring more nitrogen than dessert varieties. To put this theory into practice, simply choose any one of the methods below. And, for dessert apples, apply an additional 25g per sq m (¾oz per sq yd) of sulphate of potash every three years.
Method one: Each year, use a potassium-rich general fertiliser (rose fertiliser for example) each year in late winter as directed by the manufacturer.
Method two: Each year, use Growmore fertiliser. Apply 100g per sq m (3oz per sq yd) for dessert apples in bare soil and 140g per sq m (4oz per sq yd) for dessert apples in grass. For cooking apples, use 50 percent more.
Method three (organic alternative): Use the weights stated in method two, but substitute Growmore with dried poultry manure pellets. Organic potassium (instead of sulphate of potash) can be used every three years.
Pears, cherries, plums, gages, damsons and peaches
- These fruits need a balanced general fertiliser in early spring. As a result, sprinkle Growmore around the root zone at the rate of 140g per sq m (4oz per sq yd)
- Organic growers can use similar amounts of dried poultry manure pellets with some organic potassium every three years
It is worth noting that occasional soil testing is helpful in ensuring feeding regimes are effective. Testing every four years is sufficient. Click on the link for the service offered by the RHS.
Fruit trees in containers
When growing fruit trees in containers a slightly different approach is needed.
How to mulch fruit
Organic (biodegradable) mulches improve soil structure and fertility as they are drawn down into the surface layer by earthworms.
- Make sure the soil around the tree is thoroughly moist (but not sodden) before applying the mulch. Late winter is the ideal time to mulch
- Spread the mulch 7.5-10cm (3-4in) deep around the base of the tree to cover the rootball area
- Keep a mulch-free circle around the base of the tree trunk (about 7.3-10cm or 3-4in) to prevent the bark decaying
Inorganic (non-biodegradable) mulches do not improve the fertility or structure of the soil, but they do suppress weeds and conserve moisture. Shingle, pebbles, gravel, and other decorative aggregates can be used around trees. Permeable woven landscape fabrics can also be used that allow rain and irrigation water to reach the roots. Note that light coloured mulches reflect light back into the canopy which is particularlt valuable for cherries.