Bulbs
Flower Basics
Flower Beds & Specialty Gardens
Flower Garden
Garden Furniture
Garden Gnomes
Garden Seeds
Garden Sheds
Garden Statues
Garden Tools & Supplies
Gardening Basics
Green & Organic
Groundcovers & Vines
Growing Annuals
Growing Basil
Growing Beans
Growing Berries
Growing Blueberries
Growing Cactus
Growing Corn
Growing Cotton
Growing Edibles
Growing Flowers
Growing Garlic
Growing Grapes
Growing Grass
Growing Herbs
Growing Jasmine
Growing Mint
Growing Mushrooms
Orchids
Growing Peanuts
Growing Perennials
Growing Plants
Growing Rosemary
Growing Roses
Growing Strawberries
Growing Sunflowers
Growing Thyme
Growing Tomatoes
Growing Tulips
Growing Vegetables
Herb Basics
Herb Garden
Indoor Growing
Landscaping Basics
Landscaping Patios
Landscaping Plants
Landscaping Shrubs
Landscaping Trees
Landscaping Walks & Pathways
Lawn Basics
Lawn Maintenance
Lawn Mowers
Lawn Ornaments
Lawn Planting
Lawn Tools
Outdoor Growing
Overall Landscape Planning
Pests, Weeds & Problems
Plant Basics
Rock Garden
Rose Garden
Shrubs
Soil
Specialty Gardens
Trees
Vegetable Garden
Yard Maintenance
Controlling a Hydrangea's Size
Controlling a Hydrangea's Size. It's hard to imagine that cute little mophead as a big shrub. Gardeners who turn a blind eye to their young shrubs' projected mature height may plant them inappropriately. Bigleaf hydrangeas (Hydrangea macrophylla) do not stay pot-size; they quickly grow to the size of a small car, 6 feet in height and 10 in breadth...
It's hard to imagine that cute little mophead as a big shrub. Gardeners who turn a blind eye to their young shrubs' projected mature height may plant them inappropriately. Bigleaf hydrangeas (Hydrangea macrophylla) do not stay pot-size; they quickly grow to the size of a small car, 6 feet in height and 10 in breadth in U.S. Department of Agriculture plant hardiness zones 6 though 9. Smaller cultivars exist, but the key is to know the mature size of the plant and situate it accordingly. If you don't, you'll need to prune the hydrangea every year for the rest of its life.
Things You'll Need
Garden clippers
Clean rag
Denatured alcohol
Prune just after the flowers fade in summer if your hydrangea blooms on old wood. These hydrangeas develop buds for the following year in August or September. Bigleaf and oakleaf (Hydrangea quercifolia, USDA zones 5 though 9) flower on old wood, and this group includes the popular mopheads and lacecaps.
Prune between summer and early spring if your shrub flowers on new wood. Panicle hydrangea (Hydrangea paniculata, zones 4 through 7) and smooth hydrangea (Hydrangea arborescens, zones 4 though 9) bud on current growth.
Wipe the blades of your clipper with a rag soaked in denatured alcohol before you begin pruning and between clips. Prune out dead stems and branches at their point of origin. Clip off crossing branches to eliminate rubbing wounds. Remove damaged stems and branches at least 6 inches into healthy wood.
Prune out several of the oldest, tallest hydrangea stems at ground level. Remove up to one-third of the total number of stems to reduce the size of the shrub. This type of pruning also rejuvenates the plant by making room for new, green shoots to take the place of the older stems removed.
Clip every stem to the ground in the autumn if your hydrangea blooms on new wood. This produces a shorter bush and bigger flowers the following spring. The severe pruning weakens the plant's support over time and can cause it to flop over under the weight of its flowers. So alternatively leave 18 to 24 inches of stem when you clip to give the plant a more solid foundation.
Tips & Warnings
If you do not know the name of your hydrangea species, you can determine if your hydrangea blooms on old wood by considering when it flowers. Shrubs that flower on old wood are those that bloom in early summer. Shrubs that flower on new wood start blooming in midsummer.
Diseased stems and branches should not go in the compost. Burn them or throw them in the trash.
