In June the garden reaches its natural high point. Roses are at their best, flowers are in their first flush, and greenery will never look more pristine. Enjoy it – but remember that a garden can peak too early.
If you haven't done so already, plant out summer bedding and plants that will provide for you later in the season. Carefully placed pots can cover for early-flowering shrubs and perennials. Pot-grown dahlias and annuals are perfect fillers if you suddenly find you have a hole after the first flush of perennials are over, so wade in and plug the gaps. Watch out for slugs and snails, and water if it is dry to help with establishment.
Mind the gaps
The early perennials can leave gaps once they are over, and many can be cut to the base to encourage new growth and in some cases a second flush of flower. Oriental poppies are a perfect example, but after providing so handsomely can wither to almost nothing. I often grow a batch of Tagetes or pot-grown sunflowers to cover the gap, but the early-flowering geraniums and plants, such as alchemilla and valerian, will regenerate. Spent growth can be put on to the compost and new growth encouraged with a can of water.
Early biennials such as forget-me-not and honesty can overwhelm summer plants. Leave only as many as you need for seeding next year. Angelica, Myrrhis odorata and valerian can be a delight in the herb garden, but be careful not to let them drop all their seed, as you will be inundated next year. Apply the June cut-back just before the seed drops. Plug gaps with calendula seed, which will be in flower in late summer if sown now.
Outdoor tomatoes, courgettes and runner beans should be planted out now. Early June is also the perfect time for sowing runner and French beans, as they tend to sit and rot in cold ground. They will catch up fast with warmer weather even though it may feel late.
Sow far so good
Sow in succession, with two to three weeks between salad crops. Short rows, sown thinly, will keep you in young leaves. I am growing beetroot and peas for their tops and roots. Sowing successionally is like pacing yourself in a meal, taking small portions and going back for seconds.
Little and often is the way to go. If you have rough areas of the garden where the likes of ground elder and nettle are out of control, you can curb their advance by cutting to the base and preventing them from seeding.
Though I have only just planted my strawberry bed, I will be netting the plants to keep the birds off. The varieties that fruit all summer, such as "Mara des Bois", will be grown under cloches to keep the fruit dry, but plants grown under cover need watering, too. Soak thoroughly with a can of water after you have picked the fruit before returning the cover.
Dead-head, but leave once-flowering roses that go on to produce hips for the autumn. Avoid using chemicals as a means of preventing blackspot and greenfly. Grow companion plants such as calendula to attract hoverflies, which will feed on the aphids, and use a slow-release organic feed and foliar tonics, such as Uncle Tom's Rose Tonic or SB Plant Invigorator.
Spring bulbs need five to six weeks after flowering to replenish their resources. If you need to clear foliage, it should be safe to do so now.
Though it may be the last thing on your mind, sow spring bedding for next year. Wallflowers can be sown after the first early spuds are lifted to make the most of the space they leave behind, and primulas can be sown under glass. The Cowichan polyanthus are a selection that indulge rich garnets, indigo blue and deep purple. They can be sown now, too, and grown under glass or in a frame for planting out in the autumn.
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