Hydrangea Not Blooming? Five Fixes and a 12 Month Plan
Quick Reference: Hydrangea Not Blooming
- Most common cause: pruning at the wrong time. Old wood bloomers (bigleaf, oakleaf, climbing, mountain) are pruned only right after summer flowering.
- Second most common: late spring frost that killed the flower buds while the plant survived. Cover with mulch or burlap ahead of hard cold.
- Light: aim for morning sun with afternoon shade. Too much shade kills the show.
- Feed: a slow release balanced 10-10-10 or a bloom booster higher in phosphorus, applied in early spring. Stop fertilizing after August.
- Water: deep watering a few times a week; soil consistently moist, not soggy.
Is your hydrangea not blooming? This is one of the most common backyard puzzles in North America, and the good news is that it is usually fixable. One of our dear readers wrote in about her 4 to 5 year old hydrangea that would not flower (from a comment left on our Planting Calendar), so we pulled together the five things most likely to be going wrong, plus practical fixes for each. Leave a comment at the bottom to let us know if any of this helps.
A little context on why this happens so often: hydrangeas grown in home gardens include four botanically distinct species that flower on different wood, so a rule that saves your neighbor’s plant can also cost you a whole season of blooms. The American Horticultural Society lists correct pruning and winter bud protection as the top two reasons for a non blooming shrub. Both are on the checklist below.
1) Pruning at the Wrong Time
Pruning at the wrong time is one of the most common culprits. First, identify your hydrangea variety to understand its pruning needs. Hydrangeas are classified by whether they bloom on “old wood” (last year’s growth) or “new wood” (this year’s growth). Here are the types and their pruning needs:
- Old Wood Bloomers: Bigleaf hydrangeas (Hydrangea macrophylla), oakleaf hydrangeas (Hydrangea quercifolia), climbing hydrangeas, and mountain hydrangeas. These should only be pruned immediately after they finish flowering in the summer. Never prune an old wood hydrangea in the fall, winter, or early spring, because you would be cutting off the buds for the upcoming season.
- New Wood Bloomers: Smooth (Hydrangea arborescens) and panicle (Hydrangea paniculata) hydrangeas may be pruned in late winter or early spring because they will produce new growth and new buds later in the season.
- Reblooming Varieties: Some newer varieties, like “Endless Summer,” bloom on both old and new wood. These typically require little to no pruning.
If you are unsure which hydrangea variety you have, it is best to stop pruning for a year or two and see if that helps. When in doubt, remove only the dead canes at ground level in early spring and leave the rest until you can identify the species.
Quick ID guide
| Variety | Blooms on | Prune when | Common tell |
|---|---|---|---|
| Bigleaf (H. macrophylla) | Old wood | Right after summer flowering | Mophead or lacecap blue or pink blooms |
| Oakleaf (H. quercifolia) | Old wood | Right after summer flowering | Oak-shaped leaves, cone shaped white flowers |
| Smooth (H. arborescens) | New wood | Late winter or early spring | Large white heads, “Annabelle” is the classic cultivar |
| Panicle (H. paniculata) | New wood | Late winter or early spring | Cone shaped white to pink blooms, sun tolerant |
| Reblooming (e.g. “Endless Summer”) | Both | Little pruning needed | Blooms twice, spring and late summer |
Any questions? Contact questions@farmersalmanac.com
2) Lack of Sun or Too Much Sun
Hydrangeas need the right amount of light to produce flowers. Most hydrangeas thrive with morning sun and afternoon shade.
Observe your plant’s location throughout the day. If it is in a very shady spot, consider transplanting it to a sunnier location (the best time for this is in the fall or early spring). If it is getting scorched by the afternoon sun, add some shade with a shade cloth or move it.
- Too much shade: while they appreciate protection from intense heat, too much shade can prevent them from forming flower buds.
- Too much sun: direct, hot afternoon sunlight can stress the plant, causing it to conserve energy for survival rather than flowering. This is especially true for bigleaf hydrangeas in warmer climates.
3) Improper Fertilization
If your soil is lacking in nutrients, the plant may not have the energy to flower. However, sometimes more is not better when it comes to fertilizer.
- Too much nitrogen: fertilizers with a high nitrogen content (the first number in the N-P-K ratio) can prioritize lush, leafy growth over blooms. Use a slow-release, balanced fertilizer (like a 10-10-10) in the early spring as new growth appears. You can also look for a “bloom booster” fertilizer with a higher phosphorus content (the middle number).
- Avoid fertilizing after August to prevent late season growth that could be damaged by frost.
4) Winter Damage
If you live in a colder climate, the extreme cold of a harsh winter or a late spring frost can kill the flower buds on old wood hydrangeas, even if the plant itself survives. The buds form in the fall and must make it through the winter to bloom the following summer. To protect your plant, cover it with a thick layer of mulch or burlap before frost. See first frost dates for your region.
The USU Extension reports that in USDA Zone 5 and colder, protecting old wood cultivars with a mulch mound roughly 12 inches deep at the base can improve next season’s bloom rate substantially compared to unprotected shrubs.
5) Other Factors to Consider
- Watering: hydrangeas are “water hogs.” Ensure your soil is consistently moist but not soggy. Deep watering a few times a week is better than frequent, shallow watering.
- Plant is still establishing: even at 4 to 5 years old, a hydrangea may still be putting more energy into developing a strong root system than into flowering. Be patient.
- Deer or other animals: deer love to eat the tender new growth, buds, and flower heads, which can completely eliminate your flowers for the season. Here are 10 flowers that deer do not like.
- Soil pH: while it primarily affects the color of the blooms, extreme pH levels can sometimes impair nutrient absorption and affect flowering. Learn more about soil in our Ultimate Guide to Natural Fertilizers.
By carefully considering these factors and making some adjustments, you should be able to encourage your beautiful hydrangea to finally show off its blossoms.
A Practical 12 Month Fix Plan
If your shrub failed to bloom this year, here is a simple month by month plan for the next twelve months. It works for any variety once you have identified it.
- Now (mid summer): Confirm species. Note bud locations along canes. Water deeply once or twice a week.
- Late summer: If it is old wood and you must prune, do it immediately after flowering. Otherwise, hands off.
- Fall: Stop feeding by August. Add 2 to 3 inches of mulch around the base. In Zone 5 and colder, mound mulch or wrap burlap.
- Winter: Leave the plant alone. Do not prune. Watch for deer browse and add a wire cage if needed.
- Early spring: Feed with 10-10-10 or a bloom booster as buds swell. For new wood varieties only, prune now.
- Late spring: Cover with a sheet on late frost nights if buds are visible. Check moisture weekly.
Hydrangea Not Blooming FAQ
Why did my hydrangea leaf out but not flower?
The plant survived, but the flower buds did not. That points to two prime suspects: pruning off old wood in fall or spring, or a late spring frost killing the buds after they formed the previous fall. Confirm your species and check your last frost date this year.
Will an old wood hydrangea ever bloom again if I pruned it wrong?
Yes. Leave it alone this season. Next summer’s flower buds form soon after this year’s flowering, so if you stop pruning until immediately after next year’s bloom cycle, you should be back on track by the following summer.
Is there a fertilizer that guarantees blooms?
No fertilizer guarantees flowers, but a slow release balanced 10-10-10 in early spring, or a bloom booster with a higher phosphorus middle number, gives the plant the raw material it needs. Skip nitrogen-heavy lawn feed anywhere near the shrub.
Can I move a hydrangea to fix its light problem?
Yes, and the best window is fall or early spring while the plant is dormant. Water deeply the day before, dig a wide root ball, and replant at the same depth in a spot with morning sun and afternoon shade. Expect a season of recovery before it flowers heavily again.
Why does my hydrangea have leaves but tiny brown buds?
Late spring frost damage. The buds formed last fall, then froze on a cold spring night. Cover the plant with a sheet on nights the forecast dips below 32 F. Panicle and smooth varieties (new wood) usually escape this problem because their buds form later.
What about the Farmers’ Almanac Best Days for pruning?
The Almanac Best Days for pruning to encourage growth follow the waxing moon; pruning to slow growth uses the waning moon. Cross reference with the species rule (right after bloom for old wood, late winter or early spring for new wood) and pick the best matching date.
Join the Discussion
Do you have any tips for making hydrangeas bloom to share with our community?
We would love to hear about your experience and wisdom.
Please feel free to share photos of your beautiful hydrangeas in the comments.
Janine Pineo
Janine Pineo has been gardening all her life in Maine and writing about it for more than two decades. More of her writing can be found on her website, GardenMaine.com.
This article was published by the Staff at FarmersAlmanac.com. Any questions? Contact us at questions@farmersalmananac.com.
-
Farmers' Almanac Staff
-
Farmers' Almanac Staff
-
Farmers' Almanac Staff
-
Farmers' Almanac Staff
A friend gave me a large hydrangea that she dug out of her yard. She said it had never bloomed. As I was looking at it I noticed it looked like more than one plant tangled together. I separated it into 5 plants. The first year I was thrilled when I got one very small bloom. It has bloomed every year since then.
My hydrangea has not bloomed at all. Should I cut it back in the fall, winter or early Spring?
Hi Linda, Before pruning your hydrangea, it is important to know which type you have. If you aren’t sure, you can upload a couple of photos here and we will do our best to help you identify it! Be sure to get a clear shots of the leaves and trunk/stems.