Plant These Four Bulbs in March to Bridge the Summer Flowering Gap

With four carefully selected bulb and tuber plants, you can bridge precisely this gap.

When daffodils and tulips have finished flowering, the mood in the garden can change abruptly. Areas that were full of colour are suddenly left with greenery alone. Anyone who simply waits may have a long wait ahead: life does not return until roses, perennials and summer flowers begin to perform. Gardeners who put certain bulbs and tubers into the ground in March can avoid this lull and bring flowers into summer much earlier.

Why March determines summer flowering

Timing is the key to a garden that flowers continuously. Many summer-flowering plants grown from bulbs and tubers need several weeks to shoot, establish roots and develop blooms. If they are not planted until late April or May, their first flowers can easily be pushed back into high summer.

“Planting in March brings flowering forward by several weeks – turning a sparse June into a colourful start to summer.”

Across many German-speaking regions, the suitable window opens as soon as severe frosts have passed and the soil has begun to warm slightly. This is usually from early to mid-March. It is then worth choosing four groups of plants:

• Dahlias for abundant colour from early to late summer
• Begonias for shady corners and balconies
• Lilies for fragrant, structural focal points
• Peonies as a long-term investment for future springs

Together, they ensure that the weeks after the spring bulbs have flowered are not left empty.

Dahlias: a fast route to early summer flowers

Dahlias are among the most popular summer-flowering plants. They grow from tuberous root clusters and, provided they get an early enough start, produce new blooms almost continuously from June until October.

Starting dahlias in March

The tubers cannot tolerate frost. Planting them straight into a border risks damage should temperatures drop sharply again. A two-stage approach is therefore ideal:

• In March, place the tubers in pots filled with loose compost, covering them only lightly.
• Keep the pots somewhere bright and frost-free, such as a greenhouse, conservatory or sheltered garage windowsill.

This allows the plants to form roots and their first shoots without disturbance. From mid-May, once the risk of frost has passed, they can be moved into the border with strong growth already underway. This head start generally brings flowering noticeably earlier – often in June.

Dahlias favour fertile, free-draining soil and a position in sun or light partial shade. Regular watering and an occasional feed during summer reward you with large, richly coloured flowers. Removing faded flower heads encourages a constant supply of new buds.

Begonias: a solution for shady balconies and north-facing spaces

A garden without blazing sunshine does not have to be without flowers. Tuberous begonias thrive where other plants struggle: in partial shade or shade, on north-facing balconies and in sheltered courtyard corners.

How to grow begonias from tubers successfully

In March, place the flat tubers in trays or pots with the hollow side facing upwards. The compost should be loose, humus-rich and evenly moist, but never waterlogged. Cover the tubers only lightly, or leave them exposed until the first shoots emerge.

A bright, frost-free spot is best. Once the shoots have lengthened and temperatures remain reliably mild, the plants can be moved in their pots to a balcony or patio. They will flower throughout summer, as long as they are not allowed to dry out.

“Begonias fill the flowering gap in shady areas where traditional summer flowers scarcely provide any colour.”

One important point: tuberous begonias are sensitive to cold. In autumn, lift the tubers from the compost, allow them to dry in an airy place and then overwinter them frost-free. They can then remain part of the garden for many years.

Lilies: elegant, fragrant accents between border gaps

Lilies add a different dimension to planting schemes: they grow tall, carry striking and sometimes intensely scented flowers, and introduce bold vertical lines to beds and borders. They are particularly effective at creating contrast among lower perennials and ground-cover plants.

What matters when planting lilies

Plant the bulbs in March, as soon as the soil can be worked. A few basic rules help to prevent losses:

• Planting depth: two to three times the height of the bulb
• Position: sunny to partially shaded, neither too hot nor too wet
• Soil: well drained, ideally loosened with a little sand or fine grit

Depending on the type, many varieties flower from May to August. Combining early- and late-flowering varieties extends the display, leaving scarcely any gaps in the border. Another benefit is that lilies make excellent cut flowers for a vase.

Peonies: plant now and marvel in two years

Peonies are enduring garden favourites, but they are not for impatient gardeners. Planting them in March means planning several years ahead, yet the reward lasts a long time. Once established, they often remain in the same spot for decades and become more beautiful year after year.

Long-term planning for lavish spring flowers

Whether herbaceous or tree peonies, both forms prefer deep, humus-rich soil and a site in sun or partial shade. It is essential not to plant them too deeply. On herbaceous peonies, the growth buds should sit just below the soil surface; otherwise, they can quickly refuse to flower.

“Peonies are regarded as the ‘long-distance runners’ of the garden – restrained at first, then almost impossible to imagine being without.”

During their first two to three years, newly planted specimens can appear rather weak, producing few or no blooms. Give them that time and they will later reward you with large, sometimes highly scented flower heads that define late spring and early summer.

How to close the flowering gap deliberately

The four plant types play different roles throughout the year. Combined thoughtfully, they leave hardly any period without colour. One possible border plan is:

Period	Main flowering focus
March – April	Spring bulbs (daffodils, tulips, crocuses)
May – June	First lilies, peonies, early dahlias
June – August	Dahlias, begonias, various lilies
September – October	Late dahlias, some begonias, autumn perennials

Planting in March gets this sequence under way in good time. Those who wait until late April often lose the whole of June as a flowering month, simply because the plants have not progressed far enough.

Practical tips for strong results

A few straightforward measures help ensure that the effort pays off:

• Inspect bulbs and tubers before planting, discarding any that are soft or mouldy.
• Never plant into wet, heavy soil; mix in some sand instead.
• Consider each plant’s eventual height: place low-growing varieties at the front, and taller plants such as lilies and many dahlias towards the back.
• Make sure pots and balcony planters have sufficient volume, otherwise everything dries out too quickly.

If you are unsure, start some of the tubers in pots as a trial and move them into the border later. This makes spacing easier to judge because you can already see the plants’ actual size.

What many people underestimate: spring risks and opportunities

March may sound like spring, but late frosts are still possible. Tubers in pots or shallow containers are especially prone to cooling rapidly overnight. A simple horticultural fleece cover, or temporarily moving them into a garage, prevents damage. In borders, a thin mulch layer of leaves or grass clippings offers the soil some protection.

At the same time, an early start to the year presents another opportunity: if planting reveals bare-looking beds or poorly proportioned paths, there is still time to redesign them. Perennials have not yet reached their full growth, so the space remains easy to assess. Step by step, this creates a garden that stays colourful from the first day of spring until autumn – without weeks of dreary in-between periods.