Tulips grown hydroponically are typically “forced” bulbs, meaning they have been manipulated to bloom earlier than their natural cycle through a pre-chilling period and growth in water or an inert substrate rather than soil. This forcing process requires the bulb to expend a great deal of its stored energy reserves to produce the flower. Unlike garden tulips, which naturally replenish their energy stores over the spring, the hydroponically forced bulb is left depleted. Encouraging a second bloom requires a deliberate, multi-step process to help the bulb recover and rebuild its internal nutrient supply. This guide outlines the steps for saving the bulb and preparing it for outdoor planting in the fall.
Immediate Post-Bloom Steps
As soon as the petals fade, remove the spent flower head, a process known as deadheading. Use clean snips or scissors to cut the stem just below the bloom, ensuring you do not cut any attached leaves. This prevents the plant from diverting energy toward producing a seed pod, which is energy-intensive. Remaining resources are then directed back into the bulb for storage.
The leaves must remain completely intact, even if they seem unsightly. These green structures are responsible for photosynthesis, converting sunlight into the sugars and starches the bulb needs to replenish its reserves. Once the flower is removed, carefully take the bulb, its attached leaves, and roots out of the hydroponic container and discard the water or pebbles. The bulb is now ready to be transitioned into a soil environment for recovery.
Recharging the Bulb in Soil
The next phase is the active growth period required to recharge the bulb’s reserves for future flowering. Immediately plant the bulb in a small pot using a standard, well-draining potting mix, which provides the necessary nutrients the water-based system lacked. Plant the bulb at a depth roughly three times its height, with the pointed end facing upward, as you would any container tulip.
Place the potted bulb in a sunny location, such as a bright window or a protected spot outdoors, to maximize photosynthesis. Water the soil thoroughly after planting and continue to water regularly, keeping the soil consistently moist but never waterlogged to prevent rot. This is the only time a forced bulb should be fertilized; apply a water-soluble, balanced fertilizer, such as a 10-10-10, every two weeks to help rebuild its stores.
The bulb needs several weeks of active growth to fully recover the energy spent on blooming. Resist the urge to remove the leaves while they are still green, as they are actively feeding the bulb. Wait until the foliage naturally begins to turn yellow, then brown, and finally withers completely. This yellowing indicates that the plant has finished its job and has successfully pulled all usable nutrients back down into the underground bulb.
Curing and Preparing for Dormancy
Once the leaves have completely yellowed and died back, the active growing season is over, and it is time to transition the bulb into summer dormancy. Stop watering the pot entirely and allow the soil to dry out completely. Gently dig the bulb from the soil, taking care not to damage its outer layer. Brush away excess soil and trim off the dead foliage and any remaining roots.
The bulb must then be “cured” by drying it in a cool, dark, and dry area with good air circulation for one to two weeks. This curing process hardens the bulb’s outer layer, helping to prevent fungal growth and rot during storage. After curing, store the firm, papery-dry bulbs in a breathable container, such as a mesh bag, a paper bag, or a cardboard box filled with peat moss or vermiculite.
The ideal storage temperature during the summer is between 40 and 70 degrees Fahrenheit. Keep the bulbs away from ripening fruit, such as apples, as they release ethylene gas, which can damage the bulbs and prevent future flowering. The bulb remains dormant until the fall, when it requires vernalization—the chilling necessary for the plant to form a flower bud. Tulips require 12 to 16 weeks of cold temperatures, ideally between 35 and 45 degrees Fahrenheit, before being planted outdoors in the fall. Attempting to re-force these saved bulbs indoors the following year is rarely successful, so the best chance for a second bloom is to plant them directly into a garden bed.