Weekend work: Time to plant conifers

Camassia will naturalise in grass, sending up thick blue spikes of flower in June and July

What to do

April is a good time to plant conifers, but in exposed areas, protect newly planted specimens with a windbreak until they are established. Water well.

Summer flowering bulbs, such as camassia and galtonia, are on sale now in garden centres. Both are well worth having. Camassia will naturalise in grass, sending up thick blue spikes of flower in June and July. They are happiest in heavy, damp soil. Set the bulbs 10cms deep.

If you are planting in grass, the easiest way is to start the bulbs off in pots and transplant them when the green shoots are growing strongly. Chop out turfs, about 1ft sq, and plant the bulbs in the spaces, topped up with fresh earth.

Galtonias need more mollycoddling. These summer flowering bulbs send up thick, stiff stems at least 90cms high, covered with white flowers rather like enormous hyacinths. The bulbs need to go in about 15cms deep and 30cms apart.

Trim winter flowering heathers as flowers fade, taking care not to cut back into old growths. Heathers will not break from old wood. Shears are the easiest tool for this job. Low growing branches can easily be layered to produce new plants. Scoop out a little hollow under a likely-looking growth and bend the branch into it, securing it with a hoop of wire or a small stone.

Continue to plant vegetables, where the soil is dry and easily worked. You could try the well-flavoured radish 'Sparkler' (Marshalls, £1.75), baby leeks such as 'Neptune' (Marshalls, £1.95), and the lettuce 'Amaze' (Marshalls, £2.25), like 'Little Gem' but red rather than green.

What to see

The RHS has just got to the end of a massive restructuring of its Award of Garden Merit, given to the most outstanding plants in any group. Plants are assessed during long-running trials and marks given for health, vigour, and general garden worthiness. Nearly 2,000 plants have been taken off the old list and 1,400 added. Visit rhs.org.uk/agmplants