The vibrant display of flowering bulbs marks the start of the growing season, but the care they receive after the blooms fade determines their ability to flower again next year. Bulbs are underground storage organs that use the post-flowering period to rebuild energy reserves depleted by flowering. This process involves moving photosynthesized energy from the leaves back into the bulb structure. Proper management of the spent flowers, foliage, and the bulb’s ultimate destination ensures a successful return performance.
Managing Spent Flowers and Foliage
The first step after the petals drop is to remove the spent flower head, a process known as deadheading. This action redirects the plant’s energy away from seed production, an energy-intensive process that weakens the bulb for the following season. When deadheading larger bulbs like daffodils, the entire flower should be pinched or cut off, but the green flower stalk must remain intact. Leaving this stalk allows it to continue contributing to photosynthesis, maximizing the energy stored in the bulb.
After removing the flower, the leaves must be left undisturbed until they naturally turn yellow or brown. The leaves function as the plant’s solar panels, converting sunlight into carbohydrates that are transported down to the bulb for storage. Cutting the leaves prematurely short-circuits this recharging phase, resulting in a bulb too weak to produce a flower bud for the subsequent year. Tying or braiding the foliage to neaten the garden appearance is detrimental because it reduces the leaf surface area exposed to sunlight, interfering with efficient photosynthesis.
Immediately after flowering, while the leaves are still green and actively photosynthesizing, apply fertilizer. The fertilizer should be low in nitrogen but higher in phosphorus, such as a 5-10-5 formulation, to support root and bulb development rather than excessive leaf growth. This application provides the necessary nutrients for the bulb to absorb as it rebuilds its food stores before entering summer dormancy.
Determining When to Lift Bulbs
The decision to leave a bulb in the ground or lift it depends on its hardiness and the garden’s climate. Many spring-flowering bulbs, such as daffodils, crocuses, and grape hyacinths, are hardy and can be left in the ground indefinitely to naturalize. These bulbs only require lifting when they become overcrowded, usually signaled by a noticeable decrease in flower size or uneven blooming heights. Certain varieties of daffodils and crocus may benefit from being dug up and divided about every five years to prevent resource competition.
In contrast, tender or non-hardy bulbs, including dahlias, gladiolus, and tuberous begonias, must be lifted in climates that experience freezing winter temperatures. These plants cannot survive the cold and require protection from frost to remain viable until the next planting season. Timing is determined by the foliage; bulbs should only be lifted once the leaves have completely withered and died back naturally. This browning indicates that the bulb has entered its dormant state and has finished collecting energy reserves.
If the foliage is killed prematurely by a hard frost, the bulb should be dug up within a few days to prevent rot. Lifting the bulb too early, while the foliage is still green, can injure the bulb and prevent it from storing enough starch to survive dormancy. When digging, a spading fork is recommended over a shovel, and the tool should be inserted several inches away from the plant to avoid damaging the underground structure.
Curing and Storing Dormant Bulbs
Once the bulbs are lifted, the first step in preparation for storage is curing, which involves drying them out to harden the outer skin and prevent rot. Newly dug bulbs should have excess soil gently brushed off, and any remaining dead roots or foliage trimmed away. These cleaned bulbs should be spread out in a single layer in a cool, dark, and well-ventilated location for several days to a week. A temperature range of 60–70°F is suitable for the curing period.
After the initial drying period, the bulbs should be inspected again, and any showing signs of damage, soft spots, or disease must be discarded. Only large, firm, and healthy bulbs should be selected for long-term storage to ensure successful flowering. To maintain viability during dormancy, bulbs need to be stored in conditions that balance coolness with adequate air circulation.
Ideal storage involves placing the bulbs in breathable containers, such as mesh bags, paper bags, or cardboard boxes layered with materials like peat moss, sawdust, or vermiculite. This prevents the bulbs from touching each other, which reduces the risk of moisture buildup and fungal spread. The storage environment should be cool and dry, with a consistent temperature range between 45°F and 65°F, depending on the bulb type, and away from direct sunlight.