Although you can plant hydrangeas almost anytime, the most ideal time is in the fall or spring when temperatures are milder. Planting in the fall is doubly ideal as it allows the plant time to acclimate and establish before blooming. Plant in the morning or evening and water well to avoid heat stress.
Most Hydrangeas perform best when planted in partial sun, consider a location that receives morning sun and some afternoon shade. Panicle Hydrangeas are the exception and should be planted in full sun. Avoid planting hydrangeas near trees as this creates resource competition.
On average, your new hydrangea will need about an inch of water each week. You’ll want to water deeply to encourage root growth down into the soil. Just as with any plant, the best time to water is the early morning; this ensures your plant will have enough water to make it through the heat of the day. When the weather is exceptionally hot, you will need to increase watering to prevent your hydrangea from wilting. Remember, be careful to not wet the leaves while watering as it will encourage disease.
To effectively prune your hydrangea, it is important to know what type of hydrangea you have and understand its growth habit.
Old wood hydrangeas (Big Leaf, Climbing and Oakleaf varieties) set flower buds on last years growth. The buds set in late summer/early fall and lie dormant through the winter. If your pruning goal is to maintain a compact size, prune your old wood hydrangea immediately after it has finished blooming and before it sets blooms for the next year. In late winter/early spring you should visit your shrub and make note if there are any branches with little to no buds – these old branches can be pruned back at this time to maintain a lush, tidy appearance.
New wood hydrangeas (Panicle and Smooth varieties) set their flower buds in the spring and summer during the growing season. Because these buds emerge and develop on new branches, these hydrangeas should be pruned in late winter/early spring to encourage vigorous new growth.
Harvesting cut flowers
Hydrangeas are not only beautiful in the landscape but make wonderful cut flowers as well! To harvest, use a pair of clean, sharp shears to remove the bloom. Consider the height of your vase and cut your stem long enough to reach the water. After cutting, immediately place the stem in cold water to prevent wilting. Remove lower leaves that may fall inside the vase and recut the stem under running water at an angle. Arrange your cuttings in the vase as desired.
To keep your blooms longer, mist with water and keep an eye on the water level of the vase. If you find your flowers dramatically wilting you can place them upside-down in cool water for 10 minutes to refresh.