What Bulbs Can You Plant in March?
March marks a significant turning point in the gardening calendar, offering a window to plant bulbs that will deliver spectacular displays throughout spring and into summer. While many autumn-planted bulbs have already emerged, this month is ideal for sowing varieties that require a period of chilling or those destined for later blooming.
- Plant summer-flowering bulbs that need chilling.
- Sow hardy annuals and some perennials from seed.
- Prepare beds for later plantings and existing bulbs.
- Consider bulbs for containers and borders now.
The key to successful March planting lies in understanding which bulbs benefit from the soil warming slightly or which require specific conditions. Many summer-flowering bulbs, such as dahlias and gladioli, are tender and need to be planted after the last frost, but March is the perfect time to get them started indoors or in a protected environment if they require a head start.
Tender Bulbs Ready for Early Planting
For those in milder climates, or if you have a greenhouse or cold frame, March is an excellent month to begin planting tender summer-flowering bulbs. These plants, often originating from warmer regions, cannot tolerate frost and are typically planted out once the risk has passed. However, starting them in pots indoors or in a protected space allows them to establish roots and develop sturdy growth, ready for transplanting into their final positions later in spring.
Dahlias are a prime example. While they are often planted directly into the ground from late April or May onwards, starting them in pots in March gives them a crucial head start. Place the tubers in pots filled with well-draining compost, ensuring they are just covered. Keep them in a light, frost-free location. This method encourages early sprouting and can lead to earlier flowering and more robust plants. Similarly, gladioli corms can be planted in stages from March onwards to ensure a continuous display throughout the summer months.
Hardy Options and Preparation
It's not just tender bulbs that benefit from March attention. Many hardy bulbs and tubers that were planted in autumn or early winter may now be showing signs of life. This is the time to ensure they have adequate space and are not competing with emerging weeds. For any bulbs that were planted last autumn and haven't yet emerged, or for new plantings of hardy varieties, March soil conditions are often workable.
If you live in an area with a colder climate, you might still be able to plant some hardy perennials or even certain types of garlic and onion sets directly into the ground, provided the soil is not waterlogged or frozen. Preparing the soil is paramount; clear away any debris from the winter and incorporate well-rotted organic matter to improve drainage and fertility. This is also an opportune moment to plan your garden's layout for the coming seasons, considering where you want colour and impact.
March planting offers a crucial opportunity to extend your garden's blooming season, from the first delicate spring flowers to the bold colours of summer.
Bulbs to Plant Now for Later Enjoyment
Beyond dahlias and gladioli, consider other bulbs that thrive when planted in March. Certain varieties of lilies, for instance, can be planted now, especially if they are bare-root. Ensure good drainage, as lilies dislike sitting in wet soil. For a splash of vibrant colour, Anemone blanda, also known as Grecian windflower, can still be planted in March, although earlier is better for maximum impact. These charming, daisy-like flowers offer delicate blue, pink, or white blooms and naturalise well in woodland settings or under shrubs.
If you're looking to add structure and scent, consider planting Alliums. While many are autumn-planted, some varieties can be planted in early spring. Their architectural flower heads provide a striking visual element and are a favourite with pollinators. Remember to check the specific planting requirements for each variety, as some prefer full sun while others tolerate partial shade.
Prepare your soil thoroughly before planting any bulbs; improved drainage and added organic matter will significantly boost the health and flowering potential of your plants.
When selecting bulbs for March planting, consider their eventual height, spread, and flowering time to create a cohesive and long-lasting display. Mixing early, mid, and late-season bloomers ensures continuous interest in your garden beds and borders.
The soil temperature is a critical factor for successful bulb germination and root development, making March a timely, though sometimes marginal, planting month for certain species.
Planting Considerations for March
As March weather can be unpredictable, a few key considerations will help ensure your newly planted bulbs flourish. The primary concern is soil moisture and temperature. While the ground is likely workable, avoid planting in waterlogged conditions, as this can lead to rot.
Soil Preparation and Drainage
Good drainage is non-negotiable for most bulbs, particularly tender varieties. Before planting, fork over the soil to loosen it and incorporate compost or grit if your soil is heavy clay. For bulbs planted in pots or containers, use a high-quality potting mix that offers excellent drainage. Many summer-flowering bulbs, like ranunculus and anemones, will fail if left in soggy soil over winter or through a wet spring.
Protection from Late Frosts
While March is when many gardeners begin planting, there's still a risk of late frosts. For tender bulbs that have been started indoors, hardening them off gradually before planting them out is crucial. This involves exposing them to outdoor conditions for increasing periods over a week or two. If planting directly into the ground, keep an eye on the weather forecast and be prepared to cover newly planted areas with fleece or cloches if a sharp frost is predicted. This is especially important for bulbs that have already started to sprout.
When to Plant What
The timing of your March planting can be staggered. For tender bulbs like dahlias, starting them indoors in March is ideal. If planting directly into the ground in warmer regions, you might wait until the end of the month or early April. For hardy bulbs like Anemone blanda, planting can occur throughout March. Consider planting in batches every few weeks to extend the blooming period. For gladioli, planting a fresh batch every fortnight from March through to May will provide a succession of blooms.
Understanding the specific needs of each bulb type is vital for successful March planting, differentiating between those that need warmth and those that can tolerate cooler conditions.
Label your plantings clearly, especially when planting different varieties or staggering sowings. This helps you track growth and identify plants when they are still small.
Popular Bulbs for March Planting
March is a versatile month for planting, offering opportunities for both immediate growth and future displays. Here are some popular choices that can be planted now, with considerations for their ideal conditions.
Summer-Flowering Bulbs to Start Indoors
These require protection from frost and a head start:
- Dahlias: Available in countless colours and forms, dahlias are a summer garden staple. Plant tubers in pots filled with compost, keeping them in a bright, frost-free spot.
- Gladioli: Plant corms in succession from March through to May for a continuous supply of striking spikes. They prefer well-drained soil in a sunny position.
- Begonias: Both tuberous and fibrous rooted begonias can be started now. They thrive in partial shade and provide abundant blooms, perfect for containers or borders.
- Cannas: For a tropical feel, start canna rhizomes in pots indoors. They need warmth and plenty of sun once planted out after the last frost.
Hardy Bulbs and Perennials for Direct Planting
These can often go directly into the ground if soil conditions permit:
- Anemone blanda: These small, daisy-like flowers are excellent for naturalising under trees or in rock gardens. Plant tubers about 5cm deep.
- Lilies (some varieties): Bare-root lilies can be planted now. Ensure they are in well-drained soil, and plant them at the depth recommended by the supplier, typically two to three times the bulb's height.
- Alliums: Ornamental onions provide architectural interest. Plant bulbs in well-drained soil in a sunny spot for late spring and early summer flowers.
- Spring-flowering bulbs that are already emerging: If you see shoots, ensure the soil is clear of weeds and that they have enough space.
Vegetables and Herbs from Sets/Seedlings
While not strictly 'bulbs', March is also key for planting vegetable sets and starting herb seeds:
- Onion sets and Shallots: Plant these directly into well-prepared soil.
- Potatoes: If not already chitted, March is a good time to plant early potato varieties.
- Garlic: Hardy varieties can still be planted in early March.
When choosing what to plant, consider the mature size of the plant, its light requirements, and its suitability for your soil type. This ensures a healthier plant and a more abundant bloom or harvest.
Comparing different bulb types based on their flowering times and care needs will help you create a dynamic garden display throughout the warmer months.