What to plant in March: the real start of the season

Why March is the real start

February feels like spring, but March is when your garden truly wakes up. The soil begins to warm, frost risk drops and green returns everywhere. This is the ideal time to plant perennials, sow early vegetables and work on your garden's structure.

In March you can get going with confidence. Soil temperature reaches 8 to 12 degrees, enough for roots to establish. Plant too early and roots rot in cold, wet ground. Plant too late and plants get less growing time before the dry summer months.

Perennials: the backbone of your garden

This is the month for perennials. Sage (Salvia officinalis), red valerian (Centranthus ruber), lavender (Lavandula angustifolia), cranesbill (Geranium), yarrow (Achillea millefolium) and coneflower (Rudbeckia) are all available now and establish quickly because they get the full growing season ahead of them.

Pick a dry day in March. Work compost into the planting hole, set the plant at the same depth it had in its pot, not deeper and not shallower, and firm it in well. Water thoroughly after planting. Water regularly for the first month, after that these plants largely look after themselves.

Take time over the layout. Height, flowering time and colour decide whether a bed looks good or not. Groups of odd numbers, 3, 5 or 7 of the same plant, read far stronger than single plants dotted about. Not sure which combination suits your own garden? On gardenworld.app you can see it first in an example made from a photo of your own garden.

Pre-chit potatoes for a bigger harvest

Early March is the time to pre-chit potatoes (Solanum tuberosum). This gives you a two to three week head start and means a bigger, earlier harvest.

Place the potatoes in a light spot in a box or tray: not full sun, but bright and cool, around 10 degrees. Over two to three weeks they grow short, sturdy shoots. Plant them out once the soil is less wet, usually in early April. This cuts down on rot and disease at the shoots.

Sow spring vegetables straight outside

Once soil temperature is above 8 degrees you can sow a range of vegetables directly outdoors. Carrots (Daucus carota), radish (Raphanus sativus), lettuce (Lactuca sativa), spinach, parsley and chives can all go in now. Sow in straight rows, then thin out so you do not waste scarce seed.

Cover the sown rows with garden fleece, fine mesh netting also works, against slugs and birds. Keep the soil moist, never let it dry out. The first vegetables are ready to harvest in 4 to 6 weeks.

Repair or lay a lawn

March is a good time to repair bare patches in a lawn. Mow short first, rake out dead thatch, work in some seed compost and sow grass seed thickly. Roll or firm it in well. Water regularly until the seed germinates.

Want a completely new lawn? Turf is the quicker option now, since the roots are already established, while sowing seed works better after soil preparation in April. March can still work for seed too, just make sure you water it regularly.

Shrubs and hedges: pruning and shape

The growing season really starts now. If hedging shrubs need a trim, do it now, before birds start nesting elsewhere in the garden. Prune while you can still see what you are doing and before the leaves fully close up.

For formal hedges: prune slightly narrower at the top so light still reaches the bottom. A hedge that is wider at the top than the bottom ends up with bare lower growth.

Garden tools and preparation

March is also the month to service your tools. Sharpen secateurs, check spades and rakes, and sand down rusty parts. Sharp tools work better and cause less damage to plants.

Last year's compost can go into your planting work now. If your compost is not breaking down well, check the ratio of brown to green material and make sure the heap is moist and well aerated.

What can still wait

Not everything goes in now. Heat-loving vegetables like tomatoes (Solanum lycopersicum), peppers and courgettes should wait until May. Frost-tender container plants like hibiscus (Hibiscus syriacus) and oleander (Nerium oleander) stay indoors until after the Ice Saints, 13 May.

Bare-root trees and fruit bushes can still go in early March, especially after good rain. Late August to the end of March is the right window for these.

Step by step

Step 1: Preparation

Hoe the border, remove weeds and loose clumps. Work compost or leaf mould into the top layer of soil.

Step 2: Choose and plant your perennials

Sketch or photograph your planting plan, then set each perennial at the same depth it had in its pot. Firm in and water thoroughly.

Step 3: Sow vegetables

Sow carrots, radish and lettuce in straight rows. Cover with fleece against pests.

Step 4: Plant potatoes

Set the pre-chitted potatoes in rows in late March, about 10 cm deep.

Step 5: Repair the lawn

Repair bare patches with grass seed on prepared seed bed. Roll and water regularly.

Common mistakes

A frequent mistake is planting in wet soil. Your foot sinks in, you think it will be fine, but you have just wrecked the soil structure. Plants then get poor contact with the ground and rot. Wait until it is firmer underfoot: once your foot no longer sinks in, you can plant.

Another mistake is putting potatoes into freezing cold ground. They rot there. Pre-chitting helps, but only plant them out once the soil has genuinely warmed up. Late March can work, early April is usually safer.

Sowing vegetables without thinning them is also a problem. More seed feels like more chances, but the seedlings end up thin and weak. Thin to roughly 10 cm apart so each plant has room to grow.

Plants by season in March

Each plant wants something different in March. Perennials like sage, lavender and cranesbill want to go straight into the ground now, since this is their best growing period. We pre-chit potatoes now so they are ready to plant in early April. Vegetables like lettuce grow fast, so you can keep sowing every two weeks right through to April.

Fuchsia and other container plants stay indoors until after the Ice Saints, so not in March. Shrubs like forsythia and lilac (Syringa vulgaris) can be pruned now and will quickly put on new growth. Broad beans (Vicia faba) sown back in October are growing strongly now and will flower in May and June.

Frequently asked questions

Can I put tomatoes outside in March?

No, wait until after 13 May. Tomatoes rot in cold, wet soil. Sowing indoors in February and planting out after the Ice Saints is the right approach.

My soil is still sticky and wet. Can I plant anyway?

Wait a little longer. Digging wet soil ruins its structure and gives plants a poor start. If your foot sinks into the ground, it is still too early. Wait until it has dried out more.

How deep do I plant perennials?

Set them at the same depth they had in the pot. The lightest, topmost part of the root ball should not end up under the soil.

Which vegetables grow fast enough in March?

Radish (3 weeks), lettuce (4 to 5 weeks), carrots (8 to 10 weeks). Sow every two weeks for a continuous harvest.

See it in your own garden first

Not sure if a plant will suit that spot? On gardenworld.app upload a photo of your garden and see a free preview of a spring design, complete with a plant list so you know exactly what to buy. The sharp image with plant names and sizes costs 7.99 euros, a one off payment with no subscription.