Garden Jobs for March

General garden maintenance

  • As well as being a good time to plant new shrubs, it’s also the right time to move any that are in the wrong place. Dig up as much of a rootball as possible, ensuring the plant is well watered both before and after the move.
  • Lift and divide congested herbaceous perennials as they start to show some growth. Plants such as Alchemilla mollis, Euphorbia and Sedum all really benefit from this. Dig up the clump after watering well, and with a swift sharp cut of your spade, chop the clump into two, three or four pieces, before replanting in their new positions. Using some mycorrhizal fungi or bonemeal at the base of the planting hole will ensure the roots get off to a good start. Water them in well.
  • Clean up: Even if you did a scrupulous clean up and tidy in the autumn, you’ll still find there are things to do. Scrub down paths and patios that may have grown algae over the winter months (or use a long lasting chemical treatment), rake any remaining leaves away to allow air to circulate over precious plants and grass, clean out the pond, and fix any damaged trellis or fencing.
  • If your soil is heavy with clay, dig in some well-rotted manure or clay busting compost and grit to improve its structure.
  • Prepare ground for vegetable growing by removing weeds and forking in fresh compost or manure. Cover it with black plastic if you want to warm it up for early sowing or planting.
  • Hoe away any annual weeds that are making an appearance, and carefully dig out or chemically treat any perennial weeds which are beginning to show themselves.
  • Clean up Hellebores, by cutting away old leaves, which will help prevent disease such as leaf spot and expose the flowers for you to enjoy for a little longer. Dispose of any infected leaves in general waste, not in your compost bin.
  • Cut back deciduous ornamental grasses and other perennials that were left over winter. Rake through perennial grasses. Look closely at the base of them, and be amazed at the new growth starting to come through.
  • Get plant supports in place where necessary – clumps of tall perennials will grow through the supports, all but hiding them in the summer, and remain upright rather than flopping over from the weight of flower heads, or from wind and rain. Many people leave these in place over the winter, particularly sturdy metal supports, and they make useful location markers for herbaceous perennials that disappear over winter, such as Peony, Sedum, Helenium and many more.
  • Deadhead daffodils and narcissi when they have finished flowering, and drench the leaves with a liquid feed mix in order to bulk up the bulbs for next year’s display.
  • Deadhead any bedding, such as pansies and violas, to encourage them to keep flowering.
  • Even if you mulched in the autumn, most garden beds and borders benefit from a top-up layer now. It makes the garden look tidy, will inhibit weeds and keep moisture in. If you can see weeds appearing, take them out before mulching, and also ensure the soil is moist before you cover it.
  • Start the war on slugs and snails. Whether you use chemicals or prefer to remain organically minded, start now! Set some beer traps, scatter pellets sparingly, and top up the bird feeders (they are, after all, the most eco-friendly way of keeping the slug and snail population at bay).

Containers

  • Give all your pots and containers the once-over: weed, deadhead, cut back, discard. Once you’ve done that, decide if it’s time to repot the contents into a larger pot (this should be done annually, or bi-annually if possible). If you can’t do that, scrape off as much existing soil as possible from the top of the container, and add a layer of fresh compost. Or empty the plant out of the container and shake off as much compost as you can, and repot it with fresh compost in the same container.
  • Finish off with a mulch of fine horticultural grit to help deter slugs and snails.
  • Top up raised beds and containers with fresh compost or topsoil.
  • Are you looking for new things to plant in window boxes or containers? Primulas, pansies and spring bulbs will add a splash of colour. The Small Plants range are perfect to use in pots - you could plant a small alpine collection. A collection of succulents - sempervivums and echeverias positioned in a bright sunny spot will look good all year round.

Pruning

  • Shrubs: Those grown for the colour of young stems such as Cornus, Salix (willow) and some Eucalyptus should be cut back hard to allow stems to grow for next winter. Leaving a few stems will allow some early leaf growth that will support the rest of the plant. Some Cornus have more interesting leaves than others eg Cornus alba ‘Elegantissima’ has a lovely variegated leaf so you could leave more stems to enjoy the interesting leaves later in the year.
  • Summer flowering shrubs that flower on the new growth later in the year (such as Buddlleja) can be cut right back.
  • Roses: Early spring is the right time to prune shrub and patio roses, ideally before the leaves appear. The aim is to create a strong open framework which allows good airflow and helps prevent fungal disease. First, remove any dead or diseased stems, and then cut some of the oldest stems right down to the ground. The remaining stems should be cut down by between a quarter and half, with a view to achieving a well-balanced shape when the plant grows again. Always make a slanting cut just above an outward-facing bud, sloping away from the bud. After pruning, water well, apply a granular rose fertiliser and a layer of mulch. The mulch will replace nutrients and help prevent the recurrence of blackspot.
  • Prune overgrown climbers before they spring fully into growth. Prune back to just above visible buds, and remove dead wood. Honeysuckle, ivy, winter jasmine and other vigorous plants can be cut hard back.
  • Prune early flowering clematis once the flowers are finished and before they start active growth. See our clematis care and clematis pruning notes for further details.
  • Hydrangea macrophylla (mopheads) can be pruned back to the first set of strong buds below last year’s faded flowers. Also remove a few of the oldest stems at the base.
  • Prune autumn fruiting raspberry canes down to encourage new canes.

It’s good gardening practice to give newly pruned plants a boost of nutrients as soon as possible after they’ve been chopped. A liquid or granular feed, and/or mulching with good compost or manure will ensure they recover from any shock and surge into new growth.

Growing from seed

You may want to try nasturtiums or sweet peas, basil or chives, tomatoes or lettuce, or a patch of bright wild flowers or annuals - have a go! Check our notes How to grow from seed on our website, as well as reading the notes on the packet. Decide whether you will sow the seeds inside, ready to plant out later, or directly outside when the time is right.

Planting

March is an ideal month to plant just about anything. Hold off if the ground is waterlogged or frozen, but otherwise this is a good month to start planting.

  • Get going with planting shrubs, trees, herbaceous perennials, climbers, roses, herbs and more. It can be tempting to over-plant, but a wise gardener always resists this temptation and instead allows room for growth round each new plant that is introduced. Check our Planting Instructions.
  • Plant apple, pear, cherry, plum and other fruit trees. Hard as it is to do, young fruit trees should have flowers pinched out in the first year to divert the energy into creating a good root system instead of producing fruit.
  • Plant soft fruit bushes: nothing quite beats picking your own currants,
  • blueberries, blackberries, gooseberries or raspberries, warmed by the sun, from your own garden.
  • Ensure newly planted trees are staked appropriately. When grown in pots, young trees can’t put down tap roots, so need the support of a stake for the first year or so in the ground whilst they develop this stabilizing root system. It’s important that the stake does not hold the entire tree completely rigid, though – it should come a third to half way up the trunk. The movement created by wind through the top of the tree is what sends signals to the roots to go down deeper.

Lawns

  • Get the lawnmower cleaned up and serviced if necessary as grass will begin to grow this month. Set the blades at a high level for the first few cuts and ensure you dispose of all clippings so that air, rain and fertiliser can penetrate the newly cut turf.
  • Repair any bare patches and tidy the edges. This will be an instant improvement.
  • Apply a layer of lawn dressing or a spring fertiliser to nourish and rejuvenate your lawn.
  • This is a good month to lay new turf, as well as to re-seed an existing lawn. The key is thorough preparation. See our Lawn laying information sheet for more help.
  • If you want to grow a lawn from seed, do the preparatory work now so that the ground can settle before sowing later on. Choose a seed appropriate to the light levels and usage.

Pests and disease

  • Young plant growth is vulnerable to slugs and snails. Protect with a sparse scattering of slug pellets or bait, a line of coarse sand, copper rings or tape, or slug traps baited with beer. A mulch of bark, Strulch or grit around precious plants may help, as will using coffee grounds or crushed shells.
  • Look out for lily beetle, vine weevil and other pests. Keep an eye out for aphid attacks. Broad beans, which are one of the earlier crops to sow, are particularly susceptible to black fly. Pinch out the tops to help prevent heavy infestations. It’s normally too early in March for aphid predators such as ladybirds to be doing their job. If you need to treat aphid infestations with an appropriate spray insecticide, check the label for food safety and use it responsibly without endangering beneficial insects. Think about companion or sacrificial planting near your edible crops.

Protect against frost

  • We may have cold, frosty nights through March and April, so protect young plants if low temperatures are forecast. Cloches, fleece, or cut down plastic bottles can provide cover.
  • If possible, protect fruit blossom with fleece if frost threatens.
  • Tender herbs can be kept inside on a windowsill in the sun, and placed or planted outside when the temperatures are kinder.

Wildlife

  • Birds are still in need of food and water. Keep the feeders full and a fresh supply of water in view of the house so that you can enjoy them.
  • Birds will start looking for nest sites, so be aware of them when pruning hedges and shrubs, and put a nesting box up if you haven’t got one up already.
  • Encourage other wildlife into your garden to help manage the pest populations. Leave some wood for beetles to nest in, and think about a small pond to encourage frogs, both of whom enjoy eating slugs!
  • Plant bee and butterfly friendly plants to encourage pollinators into the garden in the coming months.