Most of the commonly grown fruit trees and bushes should now be in flower
Black currants and red currants, gooseberries, plums and cherries, and most pears all flower during April.
It is a good idea to mulch around fruit trees and bushes in April, provided the ground is not bone dry when you do it. Use well-rotted manure or garden compost and spread it liberally round all fruit trees and bushes. Watering in dry weather is a must, especially for newly planted fruit trees and bushes.
If you want to try your hand at growing melons, sow them now. Sow the seeds individually in 7.5 cm (3 in) pots, and provide a temperature of not less than 18°C (65°F) the warmer the better (24-26°C / 75-80°F is optimum).
Use an airing cupboard if you don’t have a heated propagator. Germination is usually quite quick, so check the pots regularly and once the seedlings appear, move them to a light and sunny spot, and keep well watered.
Dormant strawberry plants should now be putting forth their first flush of new leaves and flower buds may start to form if the weather is mild in your area. Ensure they are well watered if the weather is dry. You can feed the plants with a high potassium fertiliser such as weak solution of tomato feed to encourage growth, but do not apply a high nitrogen feed now or the plants will just produce leaves and no flowers.
The best time to feed them is when the fruits start to form
Less feeding is required if you apply a layer of compost or well rotted manure around the plants now. This will also act as a mulch and keep moisture in.
Any strawberries that are being covered to produce early crops must be ventilated whenever the weather is warm (this could mean every time the sun is shining).
Plants will quickly suffer if it gets too hot under the cloches or tunnels. Another danger comes from pests and diseases. If they appear on covered strawberries they must be dealt with promptly. Use an organic pesticide for greenfly control that will not kill bees and other beneficial insects.
Perpetual fruiting strawberries Such varieties as ‘Aromel’, ‘Gento’ and ‘Ostara’, which are wanted for autumn fruiting, should de-blossomed until the end of May, to stop them fruiting at the same time as the summer varieties.
Frost Protection for Fruit
Keep a close eye on the weather forecast for your area as a night frost shortly before, during or after blossom will usually spell disaster and rule out the chances of fruit in the coming season. Apples are at less risk as they usually blossom in the first half of May.
Small fruit trees and bush fruits can more easily be protected from spring frosts than large trees. The simplest way is to drape horticultural fleece or even polythene over the trees and bushes on evenings when frost threatens. The signs are usually easy to interpret.
On calm and cloudless evenings, even following warm and sunny days, the temperature can drop to freezing point and below.
There are very rarely frosts when there is good cloud cover.
Remember during April to provide the delicate flowers of peaches and apricots with protection from frost. If they are wall trained, cover them at night with fine nets hung from battens and lift the nets during the day, for the benefit of pollinating insects.
Start thinning the young fruitlets of peaches and apricots, towards the end of April, as the trees produce much more than they can sensibly cope with. Thinning should take place over several weeks, starting when fruitlets are the size of large peas and stopping when they are about as large as walnuts.
Natural fruit fall from peach and apricot
Peach and apricots trees have a natural fruit fall, so if you thin over zealously to start with, you may end up with a smaller crop than you anticipated. First remove any misshapen fruitlets and those growing towards the wall, then remove one fruit from each pair.
If a fruit plant is attacked or infected and damaged early in the season, it can ruin the crop completely. As you only have one chance a year with fruit.
The pests to watch for are greenfly, capsid bugs, caterpillars, big bud mite on black currants, scab and mildew (mainly on apples and pears).
Check apples for woolly aphid, and plums for leaf-curling plum aphid. If your apples and pears have suffered from scab in previous years, spray them now.
Try to avoid spraying any fruit during the blossom-period as many beneficial insects can be affected.
Check gooseberries for any sign of American gooseberry mildew, which shows up as powdery white growth on the stems, especially new growth. Badly infected wood should be cut out and the bush sprayed once before the flowers open, again when the fruits have set and, lastly, about a fortnight later.
April is also the time to remove and burn any grease-bands put on fruit trees last autumn. Various pests-woolly aphid and winter moth, for example-will have been trapped in the sticky band while making their way up the trunks to lay eggs.