Guide written by:
John, Passionate gardener, Cambridge
March is officially the start of spring. While some frost and showers are likely, it won't be long before our gardens are filled with flowers again! Whether you're looking to broadcast sow in the ground or get your seeds going in a greenhouse, read on to find out which perennials and annuals to start sowing in March.
- Annual flowers
- Balcony plants and planters
Sowing annual flowers in March
Annual flowers stem from tiny seedlings, and grow, flower and spread their seed all in the same year.
Sowing in the ground
At this time of the year, when it is still cold during the night and on some days, sowing in the open ground will only be possible if you wait until the second half of the month. Cold-hardy plants have the ability to slow down their growth during a temperature drop before restarting at the first sign of sunshine. Want to know which flowers will bloom in May or even April? Think about the flowers you see around the countryside at this time of year: poppies, cornflowers, bellflowers, daisies and lungwort should all be naturally blooming.
Why not pick up a wild flower seed mixture to create your own flowery meadow. Simply broadcast sowing the seeds in the spring for a patchwork of beautiful flowers in a variety of colours just a few weeks later. What's more, these seed mixtures will attract insects like butterflies and bees. In addition to the species already mentioned, a wild flower seed mixture might also contain plants like tickseed, corn daisies, corncockles or malopes.
Other flower seeds worth sowing in the ground this month include: knapweeds, larkspur or the self-seeding love-in-a-mist. Sweet peas can also be grown in partial shade and borage, with its intense blue flowers, also does very well – and both are edible!
Greenhouse or indoor sowing
While planting in the ground is fairly limited during this period, many annual flowers can be sown inside to encourage early flowering (sometimes as early as May!). The selection is vast but the following varieties are readily available: nasturtiums, cosmos, zinnias, morning glories, balsams, jasmine tobacco, sweet peas, petunias, snapdragons, malopes, lobelias, touch-me-nots, and French, English and Mexican marigolds. Blanket flowers, pheasants' eye, ageratum and marguerite daisies will also do well.
Sowing in planters
You might also want to sow your annual or perennial flower seeds in pots at the start of the month. This can include things like daisies, pansies, primroses, and so on.
Sowing perennial flowers in March
Perennials are plants that remain in place and flower year after year. This is because their stems die back each year but their roots do not.
While perennials are easy enough to grow from seed, these types of plants are more commonly sold in pots. If you do decide to sow your own perennial flowers, March is not really the best time to get these started; it is better to wait for sunnier days and bear in mind that your perennials won't flower until the following year.
However, if you're looking for a summer bloom, some varieties can be sown in February or March in a mini greenhouse or indoors. Maiden pink (Dianthus deltoides), blue flax, marsh spurge, blue poppy (Meconopsis grandis) and alpine skullcap are all worth a try.
Perennial plants are almost always available in pots for easy planting. Theoretically, they can be planted all year round with the exception of frost season.
Your first perennial flowers can be sown towards the end of the month. Hollyhock, bergenia, lupine, wallflower and honeysuckle can all go in your flower beds. Fuchsias, plantain lilies, periwinkles and foxgloves will do best in partial shade while foxgloves look great in dense groups in flower beds or bordering a hedge.
For any rocky areas of the garden, go for aubrieta, candytuft or stonecrop.
You can eventually split up perennials such as larkspurs and tickseed and replant them elsewhere.
Planting bulbs in March
Spring is the best time to plant summer flowering bulbs. If you want flowers at different times (to make bouquets for example), stagger your planting cycles. You can start planting inside in March and gradually bring your bulbs outside as you need them.
As a general rule, bulbs should be planted at a depth of around 2 to 3 times their height from the top of the bulb to the surface of the soil. However, some plants, such as lily of the nile, will need to be buried deeper (about 30 cm).
Planting bulbs in the ground
Bulbs like gladioli, lilies and crocosmia can be planted towards the end of the month. However, it's best to wait until April or May to plant the other bulbs in the ground. Bulbs generally need a well draining soil. If the soil is too clay heavy, the bulbs may rot. In this case, simply add some sand.
Dig a hole with a bulb planter or spade. Avoid using a dibber to plant bulbs as these tools tend to leave a space beneath the bulb. Once you're done, add a special bulb fertiliser; do not add fresh manure!
Plant any bulbs that have flowered in pots in a corner of the garden to increase your chances of seeing them bloom next spring. This can include plants like hyacinths, daffodils, crocuses, and so on.
Planting bulbs in the greenhouse
Many summer-flowering bulbs can be planted in a greenhouse or under a polytunnel. This includes tuberous begonias, cannas, polyanthus lilies, dahlias, freesia, buttercups, arum lilies, anemones, ornamental alliums and lilies of the Nile, to name but a few.
If you decide to sow in pots, any container can be used as long as it is deep enough.
Greenhouses and polytunnels
Balconies and planters
Looking for some flowers to spruce up your balcony in March? Fill planters with cold-hardy flowers that will bloom before spring arrives. Daisies, violets, pansies and marigolds are all great options.
Lots of different types of flowers (including those grown from bulbs) can be planted in pots which can be gathered together in plant stands. Fill your containers with a mixture of 1/3 potting soil, 1/3 garden soil and 1/3 sand.
The end of the month is the perfect time to start repotting any fuchsias or ivy geraniums, or to plant or transplant nasturtiums and petunias.
A wall or a fence can easily be spruced up with climbing plants like clematis, honeysuckle or ivy.
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Guide written by:
John, Passionate gardener, Cambridge, 79 guides
When I was young, I was already working in the family garden. Perhaps that is where my interest in plants and gardening came from. So, it was logical for me to study both plant biology and agronomy. At the request of various publishers I have, over twenty-five years, written many books on the subject of plants and mushrooms (a subject that is close to my heart).They were mostly identification guides at first, but shortly after they were about gardening, thus renewing the first passion of my childhood. I have also regularly collaborated with several magazines specializing in the field of gardening or more generally in nature. There is no gardener without a garden, I have cultivated mine in a small corner of Cambridge for the last thirty years and this is where I put into practice the methods of cultivation that will I advise you in as well.