So much is happening in June that it's hard to keep up! I absolutely love this month at the end of spring, with summer just around the corner. Just think of all those extra hours you get to potter around in the evening.

You can save this time for a little light sowing of herbs, lettuce, mixed leaves as they like to germinate in cooler temperatures. Thin carrots in the evening too, to avoid the dreaded carrot root fly detecting their scent.

June is the last month to sow seeds of maincrop carrots, peas, runner/French beans and peas – although if you grow peas for the tips alone, you can carry on sowing in succession.

Do remember to keep weeding, feeding and watering. Weeds harbour pests, and you definitely want to keep these to a minimum.

If you do get an infestation of the black bean fly on your broad beans and nasturtiums, just hose them off or remove them by running your finger and thumb along the stem. A dousing of soapy water before you do this helps the process. Ladybirds will keep them in check too.

Watch out for slugs, snails, and cabbage white caterpillars, which will devour your kale leaves overnight. It's best to cover all brassica crops with a very fine horticultural net. Keep a special watch out for blackbirds as your strawberries ripen – cover them with some chicken wire.

You should be able to start harvesting other March sown crops by now – radish, spring onions, beetroot and so on. Get into the practice of immediately forking over the soil, adding compost and fertilizer, then sow another crop. Do this right up to September.

You might find this last crop will sit as small plants over the winter – and then they will grow rapidly in early spring, giving you a nice early crop next year.

If you have potatoes on the go, the early ones will be ready to harvest when the plant has the first flowers. The only way to be sure that they are ready is to dig up a few and take a look.

Garlic may be almost ready now, too. It can be harvested in the 'green' and used straight away – it'll have a wonderful sweet taste – wait till the leaves turn yellow to lift, dry and store the bulbs.

Plant out chilli and tomatoes, remembering to stake the cordon varieties of tomatoes. Remove the little side shoots that appear in the axils (between the leaves and the stem) and feed and water them for a bumper crop.

Any runners that you get from your strawberries, pin them down into the soil, or if space is tight, use another small compost-filled pot beside the plant. These will grow into small plants that will crop next year.

Other things to sow now: courgettes, chicory, Florence fennel, broccoli, turnips.

Amanda Brame is deputy head of horticulture at Petersham Nurseries, Church Lane, Petersham Road, Richmond TW10 7AB; petershamnurseries.com. You can learn more about growing an urban garden by attending one of Petersham's masterclasses.