How to Grow Hydrangeas
All hydrangeas can grow in USDA planting zones 5 to 9, but some are more cold hardy and can even grow in zones 3 and 4.
Spring and fall are the best times to plant these flowering shrubs. However, they can be planted in winter in areas where the ground is digable and in summer with plenty of water.
Most hydrangea bushes prefer some shade, especially in warmer climates. However, panicle hydrangeas and several new varieties thrive in sun.
These plants are adaptable, but thrive in moist, but well-drained, acidic, fertile soil.
If you want pink blooms amend your soil with lime to increase the pH. Apply sulfur around your plant if you want blue blooms. Sulfur will lower the pH and increase the acidity of the soil. Apply Espoma organic soil acidifier to change color from pink to blue.
Keep the soil moist, but not saturated, especially in summer and in the first year after planting. These flowering shrubs will do best with a deep watering once or twice weekly when it is hot and dry.
Applying mulch 1 to 2 inches deep is highly recommended for hydrangea plants. Mulching will cut back on watering needs, keep weeds at bay, and protect your plant in extreme temperatures. In cold climates adding some extra mulch in winter will help protect the roots.
Pruning varies amongst the different hydrangea types.
1.Old Wood Blooming Hydrangeas
Big Leaf - Mophead and Lacecap
Prune in summer or early fall when the blooms are spent. Remove up to ⅓ of the stems each year. Remove the weakest old and new shoots by pruning them at the ground or back to the main trunk.
Oakleaf hydrangeas like the Ruby Slippers Oakleaf Hydrangea do not require pruning. Trim them up lightly after they are done flowering if you want a cleaner look.
2. New Wood Blooming Hydrangeas
Prune smooth hydrangeas all the way back to the ground in winter or early spring while they are dormant.
Panicle hydrangeas don’t need pruned every year. If they are overgrown or the stems are unable to support their blooms prune the entire bush back ¼ to ½ during dormancy.
3. New and Old Wood Blooming Hydrangeas
Reblooming or Endless Blooming
These hydrangea types tend to be compact and don’t require pruning. You can deadhead spent flowers during the growing season.
Deadheading can be done on any hydrangea type at anytime. Although this isn’t necessary it creates a cleaner look and can help encourage reblooming. Trim the stem back to right above the first set of leaves below the bloom.
Now you know how to grow hydrangeas. We have armed you with the information you need to have a super healthy and happy hydrangea! Read more on Hydrangea Care.