Trees, Shrubs and Roses
Spray roses regularly against blackspot disease, especially in the damper parts of the country after wet weather. Clip vigorous hedges such as privet, lonicera and Cotoneaster lacteus.Continue to tie in the new shoots of climbing roses as they grow, for saftery reasons too. Prune early summer shrubs as they go out of flower, if necessary, such as broom and weigela. Broom can be pruned by cutting back the flowered shoots to with in about 5cm immediately after flowering. Otherwise, thin out shrubs rather than shorten back every branch. Thinning of branches achieves a size reduction but does not change the shape of the shrub or interferes with flowering too much.
Bedding plants should be planted out now, if the weather is not too cold. Be sure to water the young plants immediately after planting out and every few days, until they are actively growing, unless there is heavy rain. A liquid feed will encourage rapid establishment of bedding plants, feeding the plants as their roots grow out. Watch for slug and snail damge in the first few weeks after planting and hoe weed seedlings when small. There is still time to sow some seeds of hardy annual flowers for late summer effect, such as nasturtiums.
Continue regualr mowing, but mowing will become less as the period of vigorous grass growth passes. Feed the lawn grass if it has not grown well and looks pale. Keep the edges around kerbs and flower beds or borders trimmed to maintain a neat appearance. If you wish to control lawn weeds, good results will be achieved at this time of year, using lawn weedkillers, providing there is good growth.
Fruit, Vegetables and Herbs
Plant out tender vegetables such as sweet corn, outdoor tomatoes and runner beans in mild areas or wait for warmer weather in the next two weeks. It is important to keep ahead of weeds by hoeing while they are still small and after any few days rain that brings on weeds. Repeat sow vegetables sown earlier in the year, such as lettuce, peas and carrots. Thin out vegetables that have reached suitable size, and control weeds early. There is still time to sow savoy cabbage varieties for winter and early spring use. If the weather is wet, or there is wet foliage for more than half a day, spray apple trees for apple scab; and pear trees for pear scab.
Greenhouse and House Plants
Pot up some petunias, bedding busy lizzie or bedding begonias for greenhouse decoration in summer. Continue to feed greenhouse plants strongly and to water them well and damp down Spray a grapevine with rose spray if it had mildew disease last year. House plants can be re-potted now. Plant out tomatoes, chilli peppers, cucumbers and sweet peppers in the greenhouse soil as soon as possible, if not already done, because these need to make rapid growth now.