When the show is over...
In this article, Becky explores the annual conundrum of what to do with your spring bulbs once they have gone over.
Many of us grow spring bulbs in pots to bring spring a little closer, or earlier, or even into the house. But once the flowers are over, what should we do next? There are four strategies: throw the bulbs away, ignore them and hope they will flower again next year, repot them in fresh compost, or plant them out in the garden. Best results for showy pots are obtained from new bulbs each time, but this can be costly, and is wasteful unless the bulbs are re-used.
All too often the pots are just parked out of sight and forgotten, but if you want the bulbs to have a second life, you need to help them replenish themselves. It is tempting to leave them in the same pot of spent compost and hope they will flower the following spring, but they are unlikely to perform satisfactorily. After the flowers have finished the leaves are still photosynthesising and sending nutrients back down into the bulb. Ideally, feed and water the bulbs until the leaves have gone yellow and shriveled. A high potash feed, such as tomato feed, is suitable. It will plump up the bulb and encourage development of the embryonic flower bud. Never cut off the leaves or tie them in a knot. Nipping off the developing seed heads will also help as the plant will not be wasting energy making seeds. Once the leaves have died completely, stop watering the pot and allow the whole thing to dry out. (If you need the pot for replanting with summer bedding, take out the entire mass of roots and bulbs and transfer it to a spare plastic pot.) When it is completely dry, remove the bulbs and store them in a dry, airy place ready for replanting in fresh compost, or in the garden, in the autumn.
Another option is to replant the bulbs into the garden while they are still green and fresh, but this will depend on whether you want this bulb to naturalise in your garden, and you have a suitable spot for it. Commercially grown potted bulbs, such as hyacinths and narcissi, are frequently planted much more shallowly than they would be in the ground. If you are replanting bulbs like this, remember to plant them at a depth at least three times the size of the bulb, even if this means you are burying half the leaves at the same time.
It is easier to plant out small bulbs such as crocus or grape hyacinths as the flowers fade. As well as spreading by seeds, crocus make many small offsets which will bulk up and mature better in soil than in a pot, and their foliage dies gracefully without making an ugly mess in the border. Grape hyacinths have a habit of self-seeding prolifically, sometimes to the point of becoming a nuisance. Consider this before you release them into your flower beds with their seed pods still full.
It generally takes bulbs a year or two to settle into a regular flowering habit after starting life in a pot. Tulips are more temperamental. Many varieties fail to rebloom and simply peter out completely over a couple of years. For this reason, some gardeners regard tulip bulbs as winter bedding, and discard the bulbs after a single season. Species (wild) tulips and the Darwin hybrids are more likely to reflower. This link will take you to lists of tulips which are more perennial. https://www.rhs.org.uk/plants/tulip/longer-lasting