Plant hardy bulbs for summer flowering

Where to plant summer flowering bulbs?

Most hardy bulbs with summer flowering prefer full sun exposure, which is essential for ensuring abundant and long-lasting flowering. However, some varieties can tolerate partial shade, particularly in warm regions where filtered light helps them avoid stress during the hottest hours.

These bulbs have a formidable enemy: excess moisture in winter, which can cause their roots to rot. For this reason, prioritise well-drained locations. If your garden has heavy or clayey soil, lighten it by adding gravel or coarse sand. Another tip is to plant the bulbs on a slight slope or mound to encourage water drainage.

Sunny borders, flower beds, and raised beds are good choices for planting these hardy bulbs. They integrate well among other perennial plants that protect them from strong winds without shading them, or among grasses for a natural effect. In gardens where drainage is difficult, consider pot or container cultivation, which allows for better moisture control and the ability to move the bulbs according to their needs.

When to plant them?

Summer-flowering bulbs are generally planted in spring, in April-May, once the risk of frost has passed and the soil begins to warm up. This allows them to take advantage of ideal conditions to establish roots and grow before starting their summer flowering. In regions with milder climates or for the hardiest bulbs, planting is possible in autumn, between September and November, when the soil is still a bit warm but temperatures begin to drop. This period allows the bulbs to root before winter arrives, ensuring more vigorous growth in spring and optimal flowering in summer.

How to plant them?

Planting hardy bulbs with summer flowering is simple and can be done in a few steps to ensure optimal flowering. Here are the steps to follow:

• Prepare the soil: Choose a well-drained location, preferably in full sun. Loosen the soil to a depth of about 20 cm to facilitate rooting, and if the soil is clayey, incorporate gravel or coarse sand to improve drainage.
• Dig holes to the correct depth: Generally, plant the bulbs at a depth equivalent to two to three times their height. For example, a bulb 5 cm tall should be buried at a depth of about 10 to 15 cm. This depth protects them from temperature fluctuations and provides enough stability for healthy growth.
• Space the bulbs: To prevent the plants from competing with each other, leave enough space between each bulb. On average, an ideal spacing of 10 to 15 cm between each bulb is recommended, but check the specific recommendations for each species.
• Plant the bulb the right way up: Position each bulb with the tip facing upwards, as this is where the new shoots will emerge from.
• Cover and lightly firm: Fill the holes with soil, then gently firm it down to secure the bulbs in place. All that’s left to do is water (without overdoing it, especially if the soil is still moist in spring).

How to care for them?

Rustic bulbs with summer flowering are generally low-maintenance, but simple and regular care ensures a generous flowering year after year. Here are some tips for proper maintenance:

• Water moderately during the growth season, slightly increasing watering during periods of intense heat or drought. Bulbs do not like excess moisture, so ensure that the soil is dry on the surface before watering again.
• Apply fertiliser in spring, when the bulbs begin to emerge from the soil. A balanced fertiliser or an organic amendment (compost, well-decomposed manure) will promote abundant flowering. Renew a small dose of fertiliser during the flowering period to support the plant.
• Keep the base of the bulbs clear of weeds to avoid competition for nutrients. An organic mulch, such as pine bark or compost, can be applied around the bulbs to retain moisture, limit weeds, and protect the bulbs from cold in winter.
• Cut faded flowers as they appear to encourage new blooms and prevent the plant from exhausting its energy in producing seeds. However, leave the leaves in place until they naturally yellow, as they provide nutrients to the bulb for the following season.
• In regions with harsh winters, a thick mulch (straw, fallen leaves) can help protect the bulbs from frost. For the most sensitive varieties, additional protection with a winter cover is recommended, or you can dig them up and store them in a cool, dry place until spring.