March is time for a thorough ‘spring clean’ of your garden. Frosts can still be a hazard in March, so keep vulnerable plants protected at night if frost is forecast.
March winds can be ferocious so check exposed plants are well supported and remember to stay safe and well wrapped up whilst gardening.
Weed and dig over your borders incorporating as much organic matter as you can – those winds will help to dry out the soil. Then mulch the bare soil and remove moss and weeds from paths, terraces and driveways.
Make new beds and borders
Mark the shape with sand trickled from a bottle, remove the top layer of growing vegetation and dig the ground over, incorporating as much organic matter as possible. If you’re making a bed in the lawn, remove the turf and stack it upside down somewhere out of the way – after a year or two it will rot down into compost. Alternatively chop it up and bury upside down in the planting hole a good spade’s depth down. If you just dig it in the buried grass will regrow.
Clean and repair your garden tools, book the lawn mower in for a service and check garden furniture for any rot.
When it is warm enough, treat sheds, fences and trellis with wood preservative.
Plant and move evergreen shrubs, conifers and trees. Remember to water them well until firmly rooted in. Plant evergreen hedges such as laurel, and box, and keep them well watered in dry spells. A good soak once a week is better than superficial watering on a regular basis. Feed woody plants with general purpose fertiliser – this applies to roses, trees, climbers, hedges and shrubs.
Feed acid loving plants such as camellias and rhododendrons with ericaceous feed if you are on neutral or alkaline soil. A dose of sequestered iron also helps prevent the leaves turning yellow. Mulch regularly with fresh or composted pine needles. This can acidify the ground slightly.
Finish pruning your roses and start spraying them with fungicide to ward against black spot and mildew. Repeat every fortnight until the autumn. Remember that if an infection sets in, all the stricken leaves must be burnt – do not leave them on the compost heap as this will become the perfect incubation site.
Do not remove stems with a bud at the top, but snip off old stems bearing deadheads to just above the topmost healthy bud and remove weak shoots altogether from the base. With established plants remove some of the older shoots right down to the base – this will keep the plant compact.
If it is very wet keep off the lawn as much as possible – damage to waterlogged lawns is easily inflicted and hard to rectify. When the weather improves and the lawn has had a chance to dry out, give it a first cut with the blades on the highest setting – don’t be tempted if conditions are wet. Reseed bare patches, neaten the edges with a half moon cutter or spade and remove molehills and wormcasts. If you’re planning a new lawn, start preparing the ground for seeding or laying turf. Ask for advice in your local garden centre if you are unsure of how to begin.
Plant summer flowering bulbs
Add some compost to the soil, a sprinkling of bonemeal and plant them slightly deeper than they were in the pot.
Cut down perennials that have been left standing over winter, including grasses. Lift and divide overgrown clumps of perennials and split polyanthus plants once they have finished flowering.
On the subject of perennials that will need support in the summer, get ahead of the game so poppies, peonies and delphiniums will grow through supports, rather than being trussed up conspicuously with canes and string come the moment of near collapse.
Buy young plants now for your hanging baskets and containers and pot them up the moment the last frost is over.
Galvanise your begonia, dahlia and canna tubers into action by placing stored tubers in moist, multi-purpose compost. Keep them at around 18 degrees and remember, begonia tubers go hollow side uppermost.
The corms can be planted from mid March. Plant at fortnightly intervals for a succession of blooms throughout the summer in a well drained, sunny position. Work in some compost and bonemeal, and plant 4” deep in heavy soils (with a handful of grit at the bottom of the hole), 6” deep in lighter ones.
Sow hardy annuals such as calendula, cornflower and annual poppies in drifts – remember to plant taller plants behind shorter ones. Sow sweet peas outdoors (soak the seeds overnight to improve germination) and plant out those raised under cover.
Brighten up your pots and containers with pansies, violas, primroses, cyclamen and spring heathers. Remove the top layer of soil from pot-grown shrubs and replace with fresh potting compost that contains a slow-release fertiliser.
If the weather does turn dry, remember pots and containers need watering, especially if they are near a wall and in a sheltered position.