Hydrangeas are beautiful flowers for summer arrangements, but they are difficult to keep fresh once cut. Their large, showy flower heads and thin, woody stems cause them to lose water rapidly through transpiration. Proper handling and preparation are necessary to maximize their life in a vase. The following steps focus on overcoming this water-loss challenge to ensure your blooms remain firm and vibrant.
Initial Preparation for Cut Hydrangeas
Preparing the stem is the most important step for extending the vase life of hydrangeas. Immediately after cutting the bloom, the stem should be recut on a sharp diagonal. This should preferably be done under running water or submerged in a bowl. This angled cut increases the surface area for water absorption and prevents air bubbles from entering the vascular system, which can impede hydration.
Hydrangea stems produce a sticky sap that quickly clogs the water-conducting tissues inside the stem. To counteract this, many florists dip the freshly cut end into alum powder, a common pickling spice. Alum is mildly acidic and helps clear the sap blockage, allowing water to move efficiently up to the bloom.
Another method involves dipping the bottom inch of the stem into boiling water for about 30 seconds. This brief exposure to heat dissolves the sap buildup and clears the way for water uptake. After either the alum or boiling water treatment, the entire stem should be placed in a deep container of water. Allow the stem to condition in a cool, dark place for several hours before arranging to ensure the flower is fully hydrated and firm.
Choosing the Right Vase and Water Treatment
Selecting a clean container is important, as bacteria from a dirty vase can rapidly multiply and block the stems, causing premature wilting. The vase should be large enough to hold a significant amount of water for these thirsty blooms. Hydrangeas require deep water, so the vessel must be filled to a high level to ensure the stems remain submerged and constantly supplied with moisture.
Using commercial flower food mixed into the water provides necessary nourishment and anti-bacterial agents. These solutions typically contain sugar to feed the flower, a biocide to inhibit bacterial growth, and an acidifier to help water absorption. If commercial food is unavailable, a small amount of household bleach can be used as a biocide to keep the water clean and prevent microbial growth.
The placement of the arrangement affects the flower’s longevity in the vase. Hydrangeas should be kept away from direct sunlight, which causes rapid water loss through transpiration. They must also be placed away from drafts from air conditioning or heating vents. Furthermore, keep them away from ripening fruit, which releases ethylene gas that accelerates flower aging. Maintaining a cool, stable environment helps the blooms retain moisture.
Ongoing Daily Maintenance for Long-Lasting Blooms
Maintaining water quality is an important daily task for ensuring the longevity of cut hydrangeas. The water should be changed every two days to prevent the build-up of bacteria and microorganisms that clog the stem’s vascular system. When changing the water, recut the stems at an angle to refresh the absorption surface and remove any newly formed blockages.
Since hydrangeas can absorb water through their petals, misting the flower heads with a fine spray of fresh water once or twice a day is helpful. This direct application of moisture reduces the strain on the stem to supply water needed for the massive bloom.
If a bloom begins to wilt despite daily care, it can often be revived using a full submersion technique. The entire flower head and stem should be fully submerged in a basin of cool water for 15 to 30 minutes. This allows the flower to rehydrate directly through its petals and helps push out airlocks formed in the stem. After this bath, the stem should be recut before placing the rejuvenated bloom back into fresh, clean water.