Everything about Flower Bulbs

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This article teaches you everything you need to know about flower bulbs. Flower bulbs are actually a collective term for all plants that have a bulb, corm, or rhizome underground. Flower bulbs provide much-needed biodiversity in the plant world.
Spring bulbs are planted in autumn and bloom in spring. Summer bulbs are planted in spring and bloom in summer. Lazy gardeners love naturalizing bulbs because once planted, it's increasingly enjoyable every year.

The fun thing about flower bulbs is that you forget about them after planting. Months later, something suddenly emerges from the ground, and you think, what is this? Did I plant this? Even if you don't forget, you can still eagerly await the first shoot to appear.

Flower Bulbs and Biodiversity

The greater the variety of plants and animals, the greater the diversity. The term biodiversity refers to the wide variety of plants, animals, habitats, and genes, all of which are part of a particular ecosystem. By ensuring more and varied greenery in the city and in our own gardens, we bring nature closer to home.

Plants and animals have no place in stone gardens. We can provide food in the form of nectar and pollen, preferably from as many different plants as possible. Flower bulbs play a major role in this.

Snowdrops and winter aconites provide food very early, followed by crocuses, grape hyacinths, summer snowflakes, and ornamental onions. And the summer bloomers provide food at the end of summer due to their long flowering period.

Just Wait

Flower bulbs are not for instant gratification. It's not about planting today and enjoying the flowers tomorrow. There's always a few months of rest between planting and blooming. This rest is necessary for the flower bulb, whether it's a bulb, corm, or rhizome, to develop its flowers and leaves, which are already present in its structure. Actually, it's not really rest, as there's a lot of work happening underground.

The real rest for a flower bulb comes after flowering when the bulb dies off. This dying off process must be done with care. The flower bulb has used all its energy to bloom but then needs to store enough reserves in the bulb for the next year.

After Blooming

"Bulb" is used as a collective term for:

bulbs,
corms,
rhizomes,
and all swollen roots underground.

If the bulbs do not have the opportunity to store enough reserve food, they will certainly not bloom next year. How does the bulb do this? After or during flowering, the leaves appear. These leaves provide food through photosynthesis.

Here, the leaves absorb carbon dioxide from the air, which, along with water absorbed by the roots, is converted into glucose and oxygen. This process takes place in the leaves. So, the leaves must remain until they have withered.

Only then is their task completed, and they have stored enough reserve food to bloom again the following year. After this process, they are only present underground. We can assist the bulbs by giving them some organic fertilizer after blooming.

Spring Bloomers and Summer Bloomers

Not all flower bulbs are the same. They can be divided into two groups: spring bloomers and summer bloomers. When you think of flower bulbs (better described as bulbous and tuberous plants, but that's such a long word), tulips and daffodils quickly come to mind.

The world of flower bulbs is much larger and more diverse than these two well-known groups. There is also an enormous variety within these groups.

Spring bloomers include not only tulips and daffodils, but also grape hyacinths, anemones, ornamental onions, hyacinths, crown imperials, snowdrops, winter aconites, crocuses, and many more. These spring bulbs are planted in autumn and bloom in spring.

However, there are exceptions here as well. Besides crocuses that bloom abundantly in spring, there are also crocuses that bloom in autumn.

Autumn crocuses should be planted earlier, starting from late July, to surprise people in autumn that the crocuses are blooming unusually early this year. Not really, it's a different variety.

Summer bulbs are planted in spring (from March to May) and bloom in summer. This group has a thickened root underground, allowing them to bloom quite soon after planting. They are often non-hardy plants like dahlias, cannas, tuberous begonias, gladioli, and calla lilies (Zantedeschia).

However, there are also plants that are winter-hardy and come back every year after planting, such as trilliums, lily of the valley, and Solomon's seal. So, summer bulbs are very diverse, and a criterion often indicated is that they can be (dry) traded.

There are plants that pay no attention to classifications. Take, for example, anemones. Wood anemones (Anemone nemorosa) are spring flowering bulbs. Anemones (Anemone coronaria), which you buy as mixed or single-colored bouquets from the florist, can be planted in both spring and autumn.

From bulb to flower takes 12 weeks, allowing you to grow entire series of cut flowers. Japanese anemones (Anemone japonica) are perennial plants and bloom in September.

Making Choices

Making choices can be difficult; the options are vast, and what one garden enthusiast finds beautiful may horrify another. The choice depends not only on taste but also on common sense. Don't choose something complicated if you're a lazy gardener. Don't buy meter-high dahlias with enormous dinner plate flowers for a pot. Instead, opt for low or medium-height sturdy plants.

Experiment with flower bulbs, combine all shades of blue or all shades of white, and be surprised when everything emerges above the ground.

Spring Bloomers

This group is by far the most well-known, and it's often assumed to be the only one among flower bulbs. It's no wonder because when the bulb fields are in bloom, you'll understand why they attract so many tourists. Tulips, daffodils, and hyacinths are the most famous spring bloomers, quickly followed by alliums, crocuses, fritillaries, crown imperials, lilies, irises, and many more.

It's tempting to rely solely on beautiful pictures and buy a variety of bulbs. However, it's wiser to first consider where you want to plant them and what results you want to achieve. Flower bulbs are so versatile that they can be used in many ways. Spring bloomers are planted from late September onwards.

Which Bulbs to Plant Where

Many bulbs require sunlight, but there are also bulbs that tolerate light shade. Ensure that when planting, more soil covers the bulb than the bulb's thickness, and plant lilies deeper.

Bulbs thrive in pots and containers. Choose not too tall varieties and plant them close together, but not against the sides of the container as they could freeze. After planting, place the pots under a shelter and protect them from severe frost with a layer of leaves or a piece of fleece.

Water them after planting and occasionally thereafter if the soil becomes very dry. Forget about them until they emerge above the ground, then display them proudly.

Bulbs can be excellently combined with perennial plants in the border. The most beautiful color combinations can be achieved by coordinating their flowering times. For example, instead of planting tulips as a group in the border, scatter them among the plants for an optimal effect.

Alliums are excellent border bulbs. They bloom at a time when many perennial plants are flowering, and their often less attractive foliage is hidden from view by the surrounding plants.

Opt for early bloomers when planting bulbs in the grass. They will emerge when the grass doesn't need to be mowed yet. After flowering, the grass should not be mowed for at least six weeks to ensure that the bulbs can produce enough food with their foliage for blooming the following year.

In a flower meadow that is mowed only a few times a year, it's good to plant bulbs such as crocuses, snowdrops, fritillaries, daffodils, and wild tulips.

Pick-your-own Bulbs

'Plant now, pick later' is a golden formula. In the bulb region, you often see many pick-your-own gardens where people can pick their own bouquet. Typically, these gardens feature tulips. A garden enthusiast might not often pick a bouquet from their own garden. But who's to stop you from planting a row of bulbs in a vegetable garden or allotment specifically for picking?

Naturalizing Bulbs

It's not always clear whether bulbs will bloom again the following year. With naturalizing bulbs, you don't have to worry; they come back every year. They are a category of their own.

Planted in the right spot and left undisturbed, they will return each year and even multiply through seeds and bulbs.

Examples include bluebells, snowdrops, star hyacinths, glory-of-the-snow, corydalis, wild tulips, grape hyacinths, and wood anemones. Besides naturalizing bulbs, there are also bulbs that provide multi-year blooms.

Perennial Blooming

This term is especially used with tulips. Many tulips bloom beautifully for one year only to disappear afterward and never return. You could dig up the bulbs after the bloom when the leaves have completely withered and store them in a dry, frost-free place for the winter.

However, this can lead to disappointment because the overwintering conditions are usually not optimal, or the bulbs haven't had a chance to build up their reserves in the summer. The only option then is to order new ones in the fall.

However, in recent years, growers have worked to cultivate tulip bulbs that bloom for multiple years. These bulbs need to be given a boost of organic fertilizer with a high potassium content in February or March.

Summer Bulbs

Summer bulbs are far less known than spring bulbs, yet they form an exotic explosion of colors that we can look forward to during the winter months. Summer bulbs cannot withstand frost and therefore should only be planted in the spring to enjoy them in the summer.

There are sometimes misunderstandings about what can be considered summer bulbs and what cannot, as well as whether they are frost-sensitive or not. This is also related to climate change. Summer bulbs come from other countries where it does not freeze, so a logical conclusion is to dig them up before the frost sets in.

However, consider Crocosmia, formerly known as Montbretia, which is now recognized under both names. These plants may have a small bulb underground and are sold 'dry,' but once planted in the garden, they can happily bloom for years.

Jungle Garden

Often, it's also a matter of soil type. In a not too severe winter, a dahlia on sandy soil can survive the winter, but not on clay soil. This soil is much wetter, and dahlias cannot tolerate it.

Many summer bulbs fit perfectly into a jungle garden, a garden trend that focuses on plants with an exotic appearance, featuring large leaves and/or colorful flowers. The Canna fits in perfectly here, as do the dahlia, tuberous begonia, African lily (Agapanthus), pineapple lily (Eucomis), and calla lily (Zantedeschia).

These plants, which bloom all summer long, cannot withstand frost and must be stored frost-free in winter, for example, in a box with dry peat moss or sawdust to prevent them from drying out. If the plants are in pots, they can be overwintered with the pot in a dry, frost-free place.

Bulb Viewing

Spring is the perfect time to see spring bulbs in person. And of course, the first place that comes to mind is the Keukenhof in Lisse. All bulb flowers are named there, allowing you to see which ones you find the most beautiful.

The Hortus Bulborum, the historic bulb garden in Limmen, is also definitely worth a visit. Here, you'll see a living picture book of our bulb ancestors, complete with names and years. The blooming of summer bulbs begins in July and can continue until the first frost (around late September). From July onwards, we can admire the summer bulbs in open gardens and trial gardens.

Be sure to write down the names of the most beautiful flowers in gardens full of dahlias, lilies, cannas, gladioli, and calla lilies. It takes some time before you can order them and plant them in your garden.

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