Q.I Have A White(?) Hydrangea That Doesn’t Bloom.Is There A Reason For This?
This hydrangea gets morning sun. It’s really healthy looking. I’ve tried different pruning methods. I’ve watered it and fertilized it, but it refuses to bloom no matter what I do.
The answer depends on the type/species of hydrangea:
1. Hydrangea macrophyllas that regularly fail to bloom may have one of several issues that you will need to rule out: (a) winter or early/late frosts zapped the flower buds or the stems; (b) inconsistent watering dried out the plant too much after flower buds formed near the end of Summer or in early Fall; (c) pests like deer, squirrels and-or bunnies are eating the flower buds; (d) the plant is in too dense shade; (e) the plant is being fertilized too much or too often (a single application of a general purpose, slow release, chemical fertilizer of NPK Ratio 10-10-10 should be enough for all year if the plant is grown in places where the soil has no nutrient deficiencies like sandy soils or you can feed a cup of organic compost, composted manure or cottonseed meal). All fertilizer applications should stop three months before your average date of first frost (last week in October for Zip 23834 minus 3 months = last week in August); (g) too early to be producing flower from new growth/stems in some parts of the country; (h) may need more years of growth if the plant was grown from seed or via cuttings/layering; (i) applying fertilizer late in the growing season, which keeps the plant in grow mode and early frosts then zap the stems. If your plant is a macrophylla that gets its stems zapped every winter and then all new growth starts from the crown/base in Spring, consider getting remontant hydrangea macrophyllas (referred to as reblooming hydrangeas in commercial advertising) or hydrangeas that bloom on new wood like paniculatas and arborescens, which are more bloom reliable. Remontant hydrangeas will try to bloom in Spring from last year’s stems. Then they will try to bloom in late Summer from the current year’s new stems if these get tall and old enough by the end of the growing season. Pruning -if it is ever necessary- should be done after they bloom but before mid July for VA (it varies based on where one is located).
2. Hydrangea paniculatas – (a) it may be too early for some varieties of hydrangea paniculata in many parts of the country; (b) they may be planted in dense shade; (c) they may be getting to much fertilizer; (d) deer, squirrels or bunnies may be eating the flower buds; (e) pruning the ends of stems when they are developing flower buds at the end of Spring/early-to-mid Summer; (f) may need more years of growth if the plant was grown from seed or via cuttings/layering. Do not prune after mid Spring.
3. Hydrangea arborescens –(a) planted in dense shade; (b) too much fertilizer; (c) deer, squirrels or bunnies may be eating the flower buds; (d) pruning the ends of stems when they are developing flower buds mid-late Spring/early Summer; (e) may need more years of growth if the plant was grown from seed or via cuttings/layering. Do not prune after mid-late Spring.
4. Hydrangea serrata (Mountain Hydrangea)/quercifolia (Oakleaf Hydrangea)/aspera (Rough Leaf Hydrangea)/petiolaris (Climbing Hydrangea) – similar to Hydrangea macrophylla
