All varieties of hydrangeas will flower as early as the beginning of Spring or mid-Summer through to the end of Summer, with each bloom lasting for many weeks.
The main reasons why hydrangeas aren’t blooming is excessive fertilizer and sun exposure transplant shock, water pressure, damage from frost to blossom buds, and due to hard pruning the old wood that supports the new blooms of this season’s hydrangeas.
Continue reading for more details about the reasons your hydrangeas aren’t blooming and the best way to ensure that your hydrangea blooms in abundance the next time around…
1. Too Much Fertilizer Causes Fewer Flowers
- Signs and symptoms: Hydrangea has bushy green foliage , but it has no or very few flowers.
- The reason: Over-application of fertilizers creates conditions that are rich in Nitrogen for the hydrangeas to bloom.
One of the main reasons why hydrangeas don’t bloom as often as they should is due to the use of fertilizers with high strength or excessive use of nitrogen-based fertilizers.
Excess nitrogen promotes foliage growth at the expense of flowers which is why you have to be careful when applying fertilizer to hydrangeas.
With proper cultivation of the soil before planting (amend the area of planting with plenty of soil) and frequent applications of mulch, the majority of established hydrangeas don’t require fertilizers and will flower in abundance throughout the summer.
If you own an hydrangea in a pot or your soil doesn’t retain much nutrients , then applying fertilizer could help in the health and blooming of your Hydrangea.
How to Solve It:
Reduce the use of fertilizer since nitrogen can stimulate a flurry of soft leaf growth, which is more susceptible to frost injury as and also less flowers.
If the soil in your garden is not as good or your hydrangea has a pot then applying half strength balanced fertilizer once in the spring and again in the summer, around July, is all a hydrangea needs to produce stunning blooms.
Select a general fertilizer that is a mixture that is equal in parts Nitrogen Phosphorous as well as Potassium (NPK) in order to provide the necessary nutrients that a Hydrangea needs without over-indulging the plant in nitrogen.
If you have established hydrangeas that are in well-drained soils, the most effective method to ensure that they bloom is to apply mulch to keep moisture in, and gradually add fertilizers to soil. Eventually, the hydrangea will show stunning flowers without the need for additional fertilizer application.
2. Not Enough Light for Flowering
- Signs: Poor spindly growth or slow growth, with a few blooms.
- Causes: Shade with no direct bright light or sun.
Shade can also affect the flowering of the Hydrangea.
While hydrangeas are able to bloom in shade, the majority of bloom more spectacularly in the light dappled under a canopy of trees and in the partial sunlight because this mimics the natural conditions for their growth.
Consistent shade, without sunlight or bright light can result in spindly growth on the stems as well as foliage, with only a few flowers.
What can be done to fix it?
The only solution to the issue of low lighting is by:
- Transplant the hydrangea in an area with more sun.
- Trim any hanging tree limbs that could be too large and throw too much shade on the Hydrangea.
The sun’s rays can cause a scorching of the leaves of hydrangeas (particularly when it is hot) therefore it is essential to find a balance between shade and sun with a little diffused light or only morning sunlight to allow hydrangeas to bloom to their maximum potential, without suffering under the sun.
After you’ve transplanted your flowering hydrangea, or cut back the to the plants that are hanging over, your hydrangea will show more flowers the next year.
Here’s a YouTube video on how to transplant hydrangeas successfully:
3. Pruning at the Wrong Time and Pruning too Hard Prevents Blooms
- Signs: Hydrangea that has been cut back well the previous year, but has not produced any flowers.
- Reasons: Pruning too much can damage the wood that flowers grow from.
The flowers of Hydrangeas bloom from mid- until the end of Summer (June/July through late August) on the shoots that emerge from the growth of last year.
Pruning too much to old wood sever the portion of the hydrangea from where flowers are created as well. The flowering hydrangea will not flower..
Hydrangeas don’t necessarily need annual pruning like roses do, and they still show plenty of flowers. However, regular light pruning is the ideal to encourage flowers.
When and How to Prune for Flowers:
- The ideal time to trim the hydrangeas is during the spring. To improve the chances of blooming, keep the flowers that have faded from last year’s hydrangea because they will provide the flowering buds with protection against frost during winter. However, in warmer climates where damage from frost is not a major threat, the hydrangeas may be cut at the close of winter.
- Hydrangeas are not tolerant to pruning that is hard. While hard pruning isn’t necessarily harmful for the overall health and well-being of your hydrangeaplant, it could cause it to not to bloom for as long as two years. Hydrangeas that have been hard pruned and cut back well tend to reseed with many new shoots and green leaves but without flowers.
- Reduce the previous year’s blooms to the first healthy buds on the stems in the springtime.
- While faded flowers might not appear tidy in winter they are usually an arrangement you need to make in order to have that your flowers will bloom in the spring. You could be rewarded with record-breaking flowers.
- If you find an old piece of wood that doesn’t appear to be extremely productive in terms of growing new plants or dying, then reduce the stems as far down to the bottom of the hydrangeas you can because this will encourage new growth which can then host more flowers.
Pruning hydrangeas to ensure the best flowers is simple and the plant can be tolerant in comparison to other plants, so don’t worry when you do fail to do so because the hydrangea will recover well next year.
4. Winter Frost Damage
Damage from frost, especially late frosts that occur in the spring could cause damage to the forming buds, which later change color to into brown.
This could affect the blooming of your hydrangea, and is among the reasons the hydrangeas like shade under trees, instead of windy and exposed places.
Frost that can damage the development of tender buds is among the main reasons why we remove the flower heads that were left on hydrangeas in the winter months because even though the sunk flower head may not appear neat and tidy during winter, it can serve as effective protection for the growing buds.
If you notice damaged buds from frost, make use of your secateurs to trim back the damaged frost growth to the buds that are next, as the buds in the outermost portion of the stem are the most exposed and thus more susceptible to being damaged, whereas flower buds further down the stem are usually kept.
(Read my article on ways to help revive your dying Hydrangea).
5. Moisture Stress
The soil must remain moist but free of drainage since the roots are not able to take well to soil that is saturated.
If the soil is properly prepared prior to planting (amended by a lot of organic material) and regularly applied mulch in the spring and enough shade to keep moisture in Then hydrangeas typically don’t require additional watering in temperate climates.
In hot climates, or for hydrangeas that are planted in soils that are sandy or stony, the hydrangeas may suffer from drought and dropping leaves.
The effects of drought can impact the growth of buds, and can restrict the length of time blooms last on your hydrangea.
In drought times, water the hydrangeas as often as is necessary in order to ensure that the soil remains moist to finger’s depth. Then apply mulch of compost, leaf mould, or well-rotted manure to help conserve soil moisture . The hydrangea must be able to access all the resources it needs to remain in bloom.
In addition, boggy and slow draining soils could cause issues like root rot, which does not just hinder blooms, but also kills the plant.
If your garden soil is typically sloppy and slow to drain, it’s much easier to plant the hydrangeas in a large container with lots of soil to retain moisture and improve drainage and prevent root decay.
6. Transplant Shock or Young Plants Can Affect Flowerings
If you’ve just relocated a hydrangea, or planted a new plant at a garden center, It could take one year for it to establish before it can bloom however some plants can bloom within the first year without any issues.
This is especially true for plants that were cultivated under controlled conditions at the nursery. They then are confronted with a stark contrast in light levels, temperature as well as soil and moisture levels when they are planted within your yard.
The hydrangea plant that is young or newly planted might take a while to settle in their new habitat prior to they bloom, as their energy is focused on forming new foliage and roots, and adapting to the new environment.
But as long as the they are within the following conditions, they will adapt adjust to their new surroundings and begin to bloom in a natural manner after the next year:
- Plants are in shade with a part shade.
- The soil has been amended by plenty of compost.
- It was hydrated frequently during the first year.
- The hydrangeas don’t bloom because of lack of sunlight and fertilizer too often and frost damage to the buds that are developing and also due to the cutting off the hard wood that supports this year’s flowering hydrangeas.
- Hydrangeas that have been planted recently usually flower more frequently when they are established following the first year.
- Stress caused by the drought or boggy soils could hinder the blooming of hydrangeas.
- Hydrangeas like morning sunlight or dappled light and a good quality, evenly moist soil that has been amended with compost, and careful pruning until the first buds appear in spring to bloom to their fullest potential.