The weather has been a perfect mix of sunshine and showers, and the temperature levels have been quite good in recent weeks, which has resulted in very good growth of plants of all kinds. Last autumn was warm and sunny, and long, and this undoubtedly built up the agapanthus plants for extra flowering. This is all the more noteworthy because, five years ago, many agapanthus plants were either killed or badly damaged in the two severely cold winters. But damaged plants seemed to have a few sections that survived and the whole plant grew back after two or three years.

The African blue lily is native to South Africa and, like many plants from that region, not completely hardy. It is sometimes called the blue lily of the Nile, but its origins are further south. Agapanthus can be grown inland with the risk of damage every few years but it is particularly good in coastal gardens. In cold areas, it is possible to grow agapanthus in a large pot and to take the pot into a greenhouse or under cover in winter.

The flower stems, which are fully extended at the moment, are flexible, strong and very wind-resistant. Each flower stem carries a loose cluster of small trumpet flowers that flare open at the mouth. The individual flowers are often striped on the back of the petals with a darker shade of blue. While blue is the normal colour, there are many shades, from deep water-blue to light sky blue. Most of these are the species Agapanthus campanulatus or hybrids of it. This one reaches about 60cm and loses its leaves in winter and it is likely to prove hardier than the evergreen sorts derived from Agapanthus africanus. This species is much bigger, twice the height, with a bigger flower head, often to 30cm across.

‘Blue Giant’ has rich blue flowers and reaches over one metre. ‘Blue Umbrella’ is 70cm and has well-shaped heads of light blue, nicely marked flowers. ‘Blue Storm’ has rich deep blue flowers and ‘Snowstorm’ is white, both about 50 to 60cm. There is a small version called ‘Lilliput’ with narrow grassy leaves and small flower stems to about 30cm. Though small, with less presence than the bigger varieties, it can still look well at the front of a sunny border and it is evergreen. There are some two-tones, such as ‘Charlotte’, which is pale blue with dark blue stripes. Some are greyish-white, such as ‘Silver Mist’, which retains enough blue to appear grey. Some, like ‘Enigma’, have dark-coloured stems, setting off the flowers. There is another species, Agapanthus inapertus, which has drooping, narrow, tubular flowers in deep purple. The flowers do not flare at the mouth. It looks different and is very elegant. ‘Blue Magic’ is a selection of it.

All forms are lively and attractive in flower and provide great contrast with yellow or red flowers, the blue setting off the hot colours perfectly. Some kinds start to flower as early as June, mostly July, lasting into August and sometimes September. After that, the plant makes diamond-shaped green seed pods and these last for a few months until they split and fall off.

Agapanthus likes well-drained soil but not too dry. The soil should be fertile, but not too rich. It likes a sunny spot near the front of a bed or border, although it can be tucked in further back too if it is a tall variety.

African lily looks best when used in several clumps along a border, or across facing borders, to play off each other. An established clump can be divided to make new plants for repeat planting. It is a slow spreader and very good at suppressing weeds when well established because it forms a remarkably dense mat of thick, fleshy roots. CL

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Flowers

Continue watering and feeding flowers in containers of all kinds – they should be approaching their peak. Rain has greatly encouraged weed growth so clear weeds in flower borders now, especially those growing in the middle of a clump of some plant or other. Cut seed heads of self-sowers, like alchemilla, before they shed seed.

Lawns

Lawns are looking well after mixed weather, sunshine and showers, and some lawn fertiliser could be used to set up a lawn for the rest of the summer. Keep the grass cut and the edges neat – nothing sets off flowers and shrubs as well as a neat lawn. There is time to use lawn weedkillers but not on a lawn for wildflowers.

Trees, shrubs and roses

Clip hedges of all kinds before the wood gets tough. Any heavy cutting back of shrubs should be left until the start of the growing season next year. Rambling roses should be pruned as flowers fade, removing shoots that have just flowered. Young trees and shrubs are doing well although, despite the rain, might need a soaking.

Greenhouse and houseplants

Continue watering and feeding greenhouse plants. Make sure to water plants in pots or grow-bags regularly, as these can easily dry out and this can lead to blossom-end rot of tomatoes and sweet peppers. Train and side-shoot tomatoes and pinch out the growing point soon to reduce the load.

Fruit, vegetables and herbs

Keep up the sprays for potato blight. Early varieties will generally be used up before the disease harms the tubers. Make some late sowings of lettuce and radishes. Sweet corn has grown well and shows great promise. Herbs can be used fresh or frozen when ready, such as flat-leaf parsley, tarragon and marjoram.

Good show of peas

There are very good crops of peas this year, owing to the suitable weather. While peas are nearly always reliable, they have good and bad years. They are a quick-maturing crop, the first peas can be picked 12 weeks from sowing. Though sown a little late, in the third week of April, the young pea plants got off to a flying start in early May.

Peas like warm weather but not too dry, which stops them growing and triggers early flowering. They really thrive with showery sunny weather, rather than overcast skies that slow growth. Well-grown plants carry a crop of flowers and pea pods.