Essential tasks for March
Keep your garden looking its best with our guide to essential tasks that need doing in March.
In the Flower garden
Pruning roses: Remove any dead, diseased or damaged stems from roses this month. On bush varieties, cut stems back to an outward-facing bud, shortening them by about a third or half.
Pruning shrubs: Prune away one or perhaps two flowering shoots from large mahonias each year, after flowering. This will encourage a succession of new replacement shoots to grow up from the base. Old, leggy shoots can be cut right down to ground level or you can stagger the length of stems to create a more interesting shape. The stems of dogwoods, willows, hardy fuchsias and ceratostigma should also be pruned back hard this month to encourage fresh, brightly coloured new growth. Cut down tall stems on Buddleia davidii to emerging shoots lower down the plant, shaping the shrub to control its size.
Pruning clematis: Summer-flowering clematis varieties that blossom on the current season's growth, such as Clematis 'Etoile Violette', need to have last year's growth pruned out now. Cut any tangled old stems down to a pair of new shoots near ground level as soon as possible.
Divide snowdrops: Lift and divide any congested snowdrops after flowering but while still in leaf. Carefully tease the clumps apart and replant the bulbs at the same depth they were before.
Fertilising: Sprinkle general-purpose fertiliser along the base of hedges and around trees and shrubs, followed by a generous mulch of rotted compost.
Planting begonia tubers: Plant tubers now in trays of moist compost, barely covering the top. Study the tubers carefully before planting and you will notice that they are convex on one side and concave on the other. The concave side should be uppermost in the pot. Keep them in a warm, bright position, watering when the compost dries out. Pot each one up individually when shoots are 5cm to 7.5cm (2in to 3in) long.
Trim heather: Trim winter-flowering heathers with shears to remove flower-heads and to shape the plants. Take care to remove only the blooms, never cutting back into old wood.
In the Glasshouse
Sow tender plants: Seed sowing plans should now be in full swing to raise the summer's bedding plants and tender vegetable crops, such as peppers, cucumbers and aubergines. By keeping a diary of when all the different varieties should be sown, you will be able to ensure everything stays on schedule. Most of the bedding plants that need early sowing, such as busy lizzies, lobelias and petunias, will also require extra heat to encourage speedy germination, so you might consider investing in an electric propagator.
Houseplant care: Pot on houseplants and ferns into slightly larger pots. Large-leaved plants, including rubber plants and Swiss cheese plants, will benefit from a thorough clean. Wash off dust and grime with a proprietary leaf-shine product or with cotton wool soaked in milk and water.
Plant summer-flowering bulbs: In warm greenhouses, plant pots of summer-flowering bulbs and corms, such as begonias, eucomis, achimenes and gloriosa.
Damping off: Protect your trays of seedlings from damping off by watering them with Cheshunt compound or a copper fungicide solution. Keep your seedlings growing strongly in good light.
Dahlias: Plant dahilia tubers in trays of compost to encourage shoots to grow. Any shoots that appear can be used as cuttings in trays of compost to encourage shoots to grow. Any shoots that appear can be used as cuttings.
Fuchsias: As conditions start to warm up during March, keep the compost just moist and mist over stems with a light spray of water. Dead stems can be pruned back hard. If you are not sure how far to prune, wait until you see signs of new shoots emerging near the base of the stems and prune back to just above these. Once they start to grow strongly, increase watering, feed weekly and pot up if required.
In the Kitchen Garden
Outdoor sowings: Crops to sow outdoors or under cloches include broad beans, beetroots, Brussels sprouts, summer cabbages, leeks, lettuces, hardy peas and radishes.
Tomatoes: Tomatoes are one vegetable no garden should be without. Many varieties can be grown outside in summer, with some even thriving in patio pots or hanging baskets. The earliest crops will develop on plants grown under glass, ideally in a heated greenhouse, but an unheated one will do. Tomatoes are easy to grow from seed, so start sowing now to raise indoor varieties. Sow in a heated propagator to encourage quick germination or grow on a windowsill. To raise outdoor varieties, sow later in March, potting on as plants grow. Plant them out in early June. Sowings can be made in April, but plants will flower and fruit far later than those that were sown earlier. Our guide to growing tomatoes will give you more tips.
Strawberries: Home-grown strawberries are a welcome summer treat and runners planted now should flower in order to fruit this year. Choose several different varieties to spread the harvest season from June until late summer. Rooted runners, sometimes called crowns, are best obtained from specialist fruit nurseries. Plants should be spaced 45cm (18in) apart in rows about 75cm (2.5ft) apart. When working out how much space you will need, remember that you'll need enough room to get between rows for picking. You can plant through a layer of black polythene to control weeds, but this looks rather unsightly. Covering plants with cloches will encourage earlier flowering, but do open cloches during the day to allow insects to pollinate the flowers.
Seed potatoes: Set out seed potatoes in trays and stand in a cool, bright position for shoots to form. Early varieties can be planted in March, but plant main-crop potatoes later in April.
Shallots: Plant shallot sets in March, spacing them at 15cm (6in) intervals in rows 30cm (12in) apart. When the conditions have warmed up in late March, onion sets can be planted out into a firm seedbed.
Planting trees: Finish planting bare-rooted fruit trees by the end of March. Container-grown trees can be planted out at any time of year. Follow our step-by-step guide to planting a tree.
Early blossom: Protect flowers on trained or compact fruit trees on frosty nights. Remove covers in the day for insects to reach the blooms. Hand-pollinate the flowers of peaches and nectarines with a soft brush. Outdoor trees will also benefit from a fortnightly spray against peach-leaf curl.
Rhubarb: Cover rhubarb with forcing jars or old buckets to exclude light and encourage long tender stalks.
Celery: Sow seed in pots in the greenhouse during March and April to raise plants that you can plant out from May to June.
Prepare for outdoor sowings: There is no need to dig soil deeply every year unless you want to incorporate more compost, gravel or other soil conditioners. Forking over the surface to remove old crops and weeds should be sufficient for most people. It may be worth investing in a few dozen bags of mushroom compost each year; this can simply be raked over the soil for the worms to work in over the coming weeks.
Clean greenhouses and frames: Wash frames and cloches inside and out with soapy water to clean away any build-up of dirt. This ensures maximum light passes through the glass of plastic to reach seedlings and crops at this dull time of year.
Mulch: Spread a mulch of garden compost around the base of fruit trees, shrubs and roses. Avoid piling the mulch up against their stems, as this could cause the bark to rot.
Transplant evergreens: The soil starts to warm up in March, so this is an ideal time to transplant evergreen shrubs and conifers or to plant new ones, including hedges. Planting early means new roots start to grow almost immediately, helping the plants to establish quickly.
Paths and patios: Use a pressure washer or chemical cleaner to clean paths, steps, paving and patios.
Tools: Check that mowers and garden machinery are in good working order and ready for the season ahead.
Tidy ponds: Clear away old plant debris from around the margins of ponds and use a net to scoop out any leaves that have fallen into the water.