If you haven’t started using biological controls yet then now is the time to buy them. The soil is now warm enough to use slug nematodes, vine weevil nematodes and ant nematodes.
Make sure you’ve applied slug nematodes to the soil before or straight after you sow your seeds to give the emerging seedlings the maximum protection.
Protect carrots from carrot fly. You can either cover them with fleece or put up a 60cm high barrier round them to keep the low flying pest away.
Many seeds can be sown outside in May. Alternatively you can sow them in an unheated greenhouse, heated greenhouse or even on a sunny window sill and just move them outside when large enough. You can also use cloches to provide some protection from the elements while the plants are small.
Seeds Suitable to Sow Outside: Beans, beetroot, broccoli, carrot, outdoor cucumber, lettuce, marrow, onion, peas including mangetout, pumpkin, radish, salad leaves, spinach, Swiss chard, sweetcorn, turnip.
In The Greenhouse
As the weather heats up make sure you can keep the greenhouse well ventilated. Add shading if necessary.
If you haven’t grown your own plants from seed, now is a good time to buy young plants from the garden centre such as tomatoes, peppers, cucumbers and courgettes.
It is also the time to start hardening off tender plants such as tomatoes ready for planting out at the end of the month when hopefully we’ve seen the last of the frost.
Start pinching out the side shoots on cordon grown tomatoes.
In mid May remove peach leaf curl protection from peaches, nectarines, apricots and almonds.