Unplanted Tulip Bulbs – What To Do
Just like any other bulbs, Tulips, even if unplanted, they never stop growing. You will notice this as the weather warms up, Tulip bulbs will start sprouting.
Naturally; if planted; after a Tulip completes blooming, the bulb will continue storing food until it starts shedding the leaves in the Summer. Then, the bulb will put its energy on growing roots to gather nutrients from the soil, at the same time forming new outer layers called tunics. This growing process will stop as the weather becomes cold, when plants enter their dormancy period until the next growing season in Spring.
Therefore, interrupting this cycle may cause unpleasant consequences for a Tulip. If unplanted at the right growing time, the bulbs will simply rot away after using the energy stored from last year into sprouting on their own without nutrients from the soil.
The pictures above (thanks Steve!) are exhausted Tulip bulbs that are not planted on time. The bulbs become dry, cracked, and falling apart.
What To Do
There’s no guarantee that Tulip bulbs will recover from an interrupted cycle, unfortunately. However, if you know you won’t be planting them anytime soon and worry that they will use up all their energy, try storing them in a paper bag and place them in cool, dry and dark location (not the fridge!). Spring-blooming bulbs are well-known the hardiest, so they have the longest life span living out of the ground and better chances at surviving.
Separate the good ones from the bad. Never store the rotting bulbs that are soft, with mushy spots or blackened roots together with the healthy ones.