Pests & Dideases

Vegetables

Sow direct in ground.

Dwarf French bean, runner bean, beetroot, calabrese, early carrot, summer cauliflower, lettuce, spring onion, pea, mangetout pea, radish, spinach / leaf beet, swede, turnip

Sow in Pots

Chinese cabbage, calabrese.

Brassicas can be sown in a seed bed.

Plant outdoors

Sprouting broccoli, brussels sprouts, autumn cabbage, winter cabbage, calabrese, summer cauliflower, autumn cauliflower, courgette, leek, marrow, pumpkin, sweet corn, outdoor tomato, chillies.

Harvesting

Early peas may be ready for harvest. 
Harvest salad onions, salad leaves, beetroot and radishes as they mature.

Over Wintered Japanese onions can be harvested when the tops start to fall over. 

Early potatoes may begin to be ready for harvesting.sweetcorn, calabrese, pak choi, kohl rabi, French and broad beans and carrots. 

Spring or early summer cabbages and cauliflowers planted last year will also be ready for cutting.

Continue with successional sowings of these and other salad crops.

Fruit

Harvest rhubarb stems until the end of the month, but leave crowns ‘forced’ earlier in the year to recover.

Keep wall-trained fruit, especially stone fruit, well watered during fruit set and fruit development. 

Wall-trained plums and cherries can be pruned this month.

Wait to thin plums and gages until the natural fruit drop has occurred.

Wait to thin apples until after the 'June drop'. Pears only need thinning if fruit set is heavy. Thinning can help improve the size and quality of the crop, and can prevent a cycle developing of ‘one good year followed by one bad year’ (known as biennial bearing).
Gooseberries can also be thinned - this will result in larger, dessert-quality fruits.

Hoe off or pull out raspberry suckers appearing between the rows.
Water tree, bush and cane fruit thoroughly every seven to 10 days during dry spells.

Put straw around strawberry plants to prevent soil splashing on to the fruit. If a small number of new strawberry plants are needed, you can peg down the runners that develop on existing plants

Tie-in the new canes of blackberry and other hybrid berries to prevent wind damage.

Herbs

Basil and coriander can be sown every two to four weeks until the end of June. Parsley can be 
slow to germinate, especially in warm dry weather, so don’t attempt to sow this herb once summer weather has arrived. 

Weed infested clumps may need lifting to disentangle weeds from the plant roots.

Remove any mouldy or yellowed leaves promptly, to prevent spread of grey mould and other fungal diseases.
Giving plants adequate spacing will help to improve air circulation and reduce the risk of fungal problems. 
Look out for pest problems once the weather warms up.

Around the Garden


Continue with successional sowing of salad crops, beetroot, Chinese cabbage, pak choi and radish, to ensure an even supply over the season.
Continue to earth-up potatoes not ready for harvest

Plant out tomatoes if this has not already been done. Train them up canes or string, and remove sideshoots from cordon tomatoes.
Celeriac and self-blanching celery can be planted out this month.

Outdoor ridge cucumbers can be planted out this month.

Sow French, broad and runner beans, peas, squash, sweetcorn, and outdoor cucumbers directly into prepared beds outside.

Peas need staking with pea sticks, netting, or pruned twigs from the garden.
Courgettes, marrows and pumpkins can still be sown outdoors in early June. 

Plant out other vegetables sown indoors earlier in the season, including winter brassicas and sweet peppers. Peppers can only be planted out when all risk of frost has passed.

The gaps between winter brassica plants can be used for quick-maturing catch crops, perhaps radishes or gem lettuces, as brassicas take time to grow into their eventual spacing.
Although most winter brassicas need to be sown earlier in the season, you can still sow turnips now for an autumn crop.

Hoe regularly between rows on hot days. 

Look out for blossom end rot on tomatoes and peppers.
Pinch out the top of broad beans once the lowest flowers have set. This will help prevent aphid attack.
Watch for the small holes flea beetles make on brassica seedlings.
Cover young brassica crops with nets to protect them from pigeons.
Keep carrot fly off carrots by covering them with a fine woven plastic mesh.
Ensure that crops remaining in the ground, new sowings under cloches, and any stored vegetables, are well protected from mice. 
Slugs pose a threat, and slug controls are necessary now, as always.
Pick yellowing leaves off brassicas promptly.