What to plant and sow in March

March is a transitional month in the world of gardening; it is no longer winter, but spring hasn't quite sprung either. Often, gardeners can be somewhat disoriented during this time and the urge to resume sowing seeds and planting can be hard to resist! However, you won't achieve anything by rushing things.

Spring is also the time of year when climate differences across the country are at their most pronounced. Gardening guides won't usually differenciate between regions, but bear in mind that things will generally be slightly ahead of time in the south of the country. Similarly, in mountainous areas, altitude must also be taken into account; account for a delay of around 3 or 4 days per 100 m of altitude difference.

Some cold-resistant vegetables can be started by sowing their seeds directly into the ground. Here are some examples:

• spring turnips;

• butter lettuce;

• batavia 'French crisp';

• frisée (curly endive);

• oak leaf lettuce;

• smooth peas;

• broad beans;

• carrots;

• beetroot;

• Chinese cabbage;

• spinach ;

• sorrel.

You can start sowing seeds for celery (celeriac and long-stalked celery), cabbage (summer cabbage, white cabbage, kale, brussel sprouts) and salsify. You can also sow seeds for aromatic plants, such as: 

• parsley;

• mint;

• chervil;

• sage;

• lemongrass;

• chives.

Sowing seeds in trays, pots and mini greenhouses

All summer vegetable seeds can be sown in a warm spot, indoors or in a mini greenhouse. This includes:

• tomatoes;

• peppers;

• aubergines;

• melons;

• watermelons;

• cucumbers;

• pumpkins.

Warmer parts of the country can start these at the beginning of the month. Cooler areas should wait until the end of the month as it is not likely that you'll be able to plant anything in the ground before the end of May.

Garlic, white onions, shallots, spring lettuce varieties, white cabbage and rhubarb can all be planted directly in the ground. Tarragon, chives, mint, spring onions and savory can join them... but keep your basil cosy indoors!

Plant your artichokes – or divide an existing plant – at the end of the month when the weather is warm. This is also a good time to plant asparagus.

In areas that enjoy relatively frost-free Aprils, you can plant your first early variety potatoes (such as Charlotte or Casablanca). Maincrop varieties, such as Roseval, can be planted later on allowing you to stagger your harvests.

Repotting and topdressing potted plants

Repot any non-flowering indoor plants that are becoming root bound. Any other plants can be topdressed. This process consists in removing a small amount of soil from the top of the pot and adding fresh compost; this is an especially good idea for your larger pots.

Using a crop cover to encourage growth

Using a horticultural fleece will put you about a week ahead of schedule, but it can reduce the amount of light your plants receive by up to 30%. Remember to uncover your plants and seedlings on sunny days and when the weather is milder.

Annual seed-grown flowers grow, blossom and create more seeds over the course of one growing season.

Planting in the ground  

At this time of year – when the nights and often days are still cool – flower seeds should only be sown directly into the ground in the last half of the month. Hardy, cold-resistant plants are able to slow growth when temperatures drop and pick up again when the sun comes out. You just need to take a look around wild areas to see what kind of plants are in flower from the start of May (or even April): poppies, cornflowers, blue bells, daisies and lungwort will all be out.

You can find flower seed mixes to grow a flower meadow of your own. Simply scatter the seeds in spring for a patchwork of beautifully coloured flowers. These mixes also help to attract butterflies, bees and other insects. In addition to the flowers already mentioned, they can contain other wild flowers such as coreopsis, wild chrysanthemum, corncockle and malope.

You can also try starting the following seedlings: knapweeds, larkspur, love-in-a-mist (which have lovely blue flowers and self-sows), sweet peas (can be kept in partial shade) and borage (pretty blue flowers and edible). 

Sowing seeds in a greenhouse or indoors 

If you find you can't sow a lot of seeds directly in the ground in March, plenty of annual flowers can be started in warm, indoor spots. This can allow them to blossom as early as May. Once again, you have a wide range of choice including:

• nasturtium;

• cosmos;

• zinnias;

• morning glories;

• balsam;

• flowering tobacco plants

• marigolds;

• petunias;

• sweet peas

• snapdragons;

• malopes;

• gaillardia;

• red camomile;

• ageratums;

• daisies. 

Planting annual and perennial flowers

You can start your annual and perennial flowers (such as pansies and primula) in pots from the beginning of the month.

Perennial plants stay in the ground and flower over several years. While their stems die back, their roots survive beneath the soil.

Sowing seeds indoors

While growing perennial plants from seed isn't particularly difficult, it doesn't happen often. What's more, March isn't actually the best month for this task; it's best to wait for warmer weather as flowering won't tend to happen until the next year anyway.

If you want your perennials to flower in summer, sow your seeds in a mini greenhouse or indoors in February or March. This is a good option for flowers like perennial carnations, blue flax, fuchsias and Himalayan blue poppies. 

Planting your perennial plants

Perennial plants tend to be sold in pots making them easier to plant. In theory, you can actually plant these all year round (except during frost season). Towards the end of the month, hollyhock, bergenia, lupins, mallow and pincushions can all go in your flowerbeds. Plant your fuchsias, hostas and foxgloves in partial shade. You can plant your foxgloves in tightly packed groups in a flowerbed or along the length of a hedge. Rock gardens can welcome aubreita, sweet alyssum and sedums.

You can also use this time to divide your perennial flowers, such as delphiniums and perennial coreopsis, and replant them in another spot.

Spring is the time when your summer-flowering bulbs must be planted. In order to stagger your blooms (to make bouquets, for example), space out your planting schedule. This way, you can start planting indoors in March before taking everything outside later on. As a general rule, bulbs should be planted down to a depth of at least 2 to 3 times their height from the top of the bulb up to the surface of the soil. However, some, such as lilies and agapanthus, need to be planted deeper in the ground (up to 30 cm).

Planting bulbs in the ground

Near the end of the month, you can plant your gladiolus, lilies and crocosmia directly in the ground. Wait until April or May to plant any other bulbs in the ground. Any type of soil will do as long as it has good drainage. If your soil contains a high proportion of clay, the bulb may rot. In this case, you can try adding a little sand. Dig a hole using a bulb planter or spade. Do not use a pointed spade at the risk of leaving a large space around the bulb. Do not use fertiliser: use a special bulb compost instead.

While you wait for your bulbs to pop up next spring, you can always fill out a corner of the garden with some bulbs that have already blossomed in pots (for example, hyacinths, daffodils or crocus).

Bulbs to plant indoors

A number of summer-flowering bulbs can be started in a greenhouse or cold frame:

• begonias (tuberous);

• cannas;

• polianthes;

• dahlias;

• freesias;

• ranunculus;

• arums;

• anemones;

• ornamental onion;

• agapanthus.  

It's worth nothing that, if you are planting in pots, any container will do as long as it is deep enough to accommodate the bulb.

Looking to brighten up your balcony in March? Fill out your planters with cold-hardy flowers that will blossom before the end of spring, such as daisies, violets, pansies and yellow alyssum. Many different varieties of flowers – including those grown from bulb – can be grown in pots, planters or other types of tray. Fill up your containers with a mixture made up of 1/3 fertiliser, 1/3 garden soil and 1/3 sand.

At the end of the month, you can start repotting your fuchsias and geraniums, and planting or transplanting your nastartium and petunias. You can also cover a wall, fence or trellis with climbing plants such as clematis, honeysuckle or ivy.

Having a vegetable plot or a purely decorative garden doesn't end with preparing your seedlings, planting and pruning from time to time. Over the course of the year, season after season, our expert gardening advice will assist you through all your gardening tasks. From growing veg and orchards to tidying up borders and flowerbeds, check out our other guides for more top tips!

• How to prepare your garden for spring

• How to prepare your seedlings

• Garden hose buying guide

• Soil-working tools buying guide

• Lawnmower buying guide

• How to secure your greenhouse