What are summer bulbs? And which ones are your favorites?

In (early) spring, beautiful summer bulbs are available for pre-order everywhere. But what exactly are summer bulbs? How are they different from regular flower bulbs, and what should you keep in mind when planting and caring for them?

Summer bulbs?

Actually, everyone knows summer bulbs… the question is just whether you recognize them as flower bulbs. Of course you know dahlias, gladiolus, and lilies. These are summer bulbs! In other words, summer-blooming flower bulbs, tubers, or rhizomes. These flower bulbs therefore do not bloom in the spring, but in the summer.

The best time to plant summer bulbs is not in the fall, but actually in the spring. They’ll bloom this summer and continue to bloom for a long time—often even until the first frost.

What are some popular summer bulbs?

There are many summer-flowering bulbs, tubers, and rhizomes, but these are the best-known summer bulbs and the most popular varieties:

Dahlia

Who doesn't know them? Dahlias are plants with colorful, eye-catching, and often large flowers that bloom from summer well into the fall. There are many different varieties Order Dahlias, in many shapes and sizes. The colors range from soft pastel shades to bright and vibrant hues such as red, yellow, orange, and purple. Some varieties produce flowers up to 30 cm in diameter. They thrive in full sun and well-drained soil. Dahlias look beautiful in flower beds, in pots, or in your own little flower garden.

In any case, we wouldn’t want to be without dahlias in our garden anymore!

Lily

Lilies (Lilium) are elegant, fragrant flowers with trumpet-shaped blooms. They bloom in the summer and early fall and come in a variety of colors. Lilies grow best in full sun or partial shade with well-drained soil. They’re perfect for pots or flower beds. Plant them in a spot where you can fully enjoy their delightful fragrance, such as at the edge of your patio or near the back door.

Gladiolus

Gladiolus (Gladiolus) are stately summer flowers with long stems and colorful, funnel-shaped blooms. They bloom from July through September and prefer full sun and well-drained soil. Not only are they ideal as cut flowers, but they also make a beautiful contrast or accent among the plants in your flower border.

Calla

The calla lily (Zantedeschia) is a striking yet elegant flower with a graceful, cup-shaped bloom. It blooms from spring through summer and comes in a variety of colors. Calla lilies thrive in moist, well-drained soil and prefer partial shade to full sun. They also look beautiful in pots.

Begonia

Begonia (also known as "crooked-leaf") is a beautiful plant with strikingly colored flowers. It blooms from late spring/early summer through the fall. It prefers shade or partial shade with slightly moist but well-drained soil. It’s a great way to brighten up a shady spot in your garden. Perfect for hanging baskets and pots, where the flowers cascade gracefully over the edges.

Crocosmia

Montbretia (Crocosmia) is a unique plant with bright, tubular flowers on long stems that bloom in the summer. The leaves are often sword-shaped (like those of the yellow iris), and Crocosmia thrives in full sun and well-drained soil. Crocosmia adds plenty of color and an exotic touch to your flower beds. It remains attractive long after flowering.

Planting and Caring for Summer-Blooming Bulbs

How do you plant summer bulbs? When is the best time to plant them, and how should you care for them? Check out our planting and care tips below.

When are summer bulbs available?

Summer-flowering bulbs are available in (early) spring, often as early as February or March. You can still buy summer bulbs a little later in the spring, but keep in mind that certain varieties can sell out quickly. So it’s best not to wait too long.

Can you plant summer bulbs right away?

If you've bought or ordered summer-blooming flower bulbs, keep in mind that you should Do NOT plant immediately! Summer bulbs generally cannot withstand frost and may die if frost occurs. Therefore, wait until April or mid-May to plant them in the ground, and keep them in a frost-free place until then.

You can start growing summer bulbs indoors in pots earlier. This will prevent them from sustaining frost damage. An added benefit is that the plants will bloom earlier and be more resistant to snails once they are finally planted outdoors.

How do you plant summer-blooming flower bulbs?

• Don't plant summer bulbs in the ground until late April or mid-May, so there's no longer any risk of frost.

• Check to make sure the bulbs are still in good condition and don't have any mold or rotten parts. This can certainly happen if, for example, you've stored them yourself in a frost-free place.

• Most types (such as dahlias, lilies, and gladiolas) need a sunny spot and well-drained soil.

• Plant them at a depth of about 2–3 times the height of the bulb or tuber. Dahlias can be planted shallowly.

• Water thoroughly after planting, but make sure the bulbs aren't left standing in water.

How do you care for summer bulbs?

• If a (night) frost does occur, be sure to protect your plants from it. For example, by covering them with non-woven fabric or a layer of mulch.

• Young dahlias, in particular, are a favorite of snails. Consider starting your dahlias in a snail-free area so that they’ll be a bit more resistant to snails by the time you plant them in their permanent spot.

• You can provide fast-growing (and large-flowered) varieties, such as dahlias, with support so that they grow (and remain) nice and upright.

• During the growing season, you can apply some liquid fertilizer, such as tomato fertilizer or a special fertilizer for flowering plants.

• Remove spent flowers promptly so that new flowers will continue to bloom.

• Dig up the dahlias after the first frost, then store them in a dry, dark, and frost-free place. Replant them in the spring.