Grubbing up flower bulbs
Many people ask me how to handle the bulbs after flowering. Should they be grubbed up or can you leave them in place? You can just leave most of the smaller special bulb varieties (snowdrops, crocus and akonite) in the ground. They often propagate by themselves through new bulbs or from seed. But what about tulips or daffodils?
Tulips
Unfortunately, the tulip will never spread greatly in the garden. And that applies to long-stemmed tulips as well as yet botanical or species tulips. Indeed, if you have looked at the tulip's life cycle, you know that each flowering bulb splits at the end of the growing season: the old bulb splits into a number of smaller bulbs. Only the largest of these will flower again the following season by itself. Afterwards, these, too, decay. So after a few seasons, all you will find in the place of the original bulb is a group of very small spheres. These are the so-called one-leafers. These only produce leaves and no flowers for the first five or more years. Propagation via seed is also a matter of a lot of patience with the tulip. In fact, if the tulip manages to self-seed, it will take around seven years or more for the seedling to grow large enough to flower on its own.
Naturalising tulips
Still, there are some naturalising tulips that you can simply leave in the border for several years. Indeed, there are some varieties that do not severely decay, but put all their growing power into one new bulb. The prerequisite is that the plants receive adequate light, water and nutrition for about two months after flowering. The old bulbs then rebuild a energy reserve sufficient to flower again the next year.
Daffodils
Daffodils won't spread greatly either, but you can leave them in place just fine. This is partly because the daffodil does not form as many new bulbs each year as the tulip. With the daffodil, some new bulbs gradually grow alongside the old daffodil bulb. If the number and size of bulbs located together becomes too large, the plants start competing with each other for light and nutrients. This may reduce flowering. In that case, dig up the bulbs once in the summer, separate them from each other and replant them with a bit more space. Then you can enjoy them again for several seasons.
Harvesting and storing flower bulbs
When the leaves of your bulb plants start to die (they will turn yellow or brown) dig up the bulbs. If the leaves are still a bit greenish, put the plants in a dry airy place (not in the sun) for another week if necessary. By doing so, you give the plant some extra time to store the nutrients from the leaves in the bulb. Then remove the leaves and sort the bulbs. It is better to discard damaged bulbs as they may rot during storage. They can then also infect the other healthy bulbs. Sort them by size. With tulips, only the largest bulbs will flower again the following year. From 8 to 9 cm in circumference, they will probably flower again. From a smaller bulb, the flower is also comparatively small. Then store the bulbs dry and airy (in a basket, net or jute bag, for example) and not too warm.
It is best not to plant tulips until October, when the soil temperature has started to drop. Plant the tulips in another part of the garden. You can plant the other bulbs from September onwards.