The name “oakleaf” comes from the Latin for “oakleaf,” and the oakleaf hydrangea (Hydrangea quercifolia) is a flowering deciduous shrub with huge clusters of blooms on robust stems and unusual leaves with lobes like those of an oak tree. The long-lasting flower panicles on this shrub are highly valued; they start off white and eventually become purplish pink. This multi-stemmed shrub typically reaches a height of 4 to 8 feet. It spreads by suckering and grows in an erect, rounded shape.
The oakleaf hydrangea is a good specimen plant that may also be massed in shrub borders or open woodland gardens, or it can be used as a foundation plant. These plants contrast with more delicate plants because of the coarse texture of their large leaves.
The beautiful hues of fall foliage include purple, orange-bronze, or crimson hues on the leathery leaves. Winter color and texture are also imparted by the peeling and exfoliating branches.
The plants are poisonous to people, dogs, cats, and horses, much like all hydrangeas.
Oakleaf Hydrangea Overview
| Common Name | Oakleaf hydrangea |
| Botanical Name | Hydrangea quercifolia |
| Family | Hydrangeaceae |
| Plant Type | Shrub |
| Mature Size | 4-8 ft. tall, 4-8 ft. wide |
| Sun Exposure | Full, partial |
| Soil Type | Moist, well-drained |
| Soil pH | Acidic |
| Bloom Time | Spring, summer |
| Flower Color | White, pink |
| Hardiness Zones | 5-9 (USDA) |
| Native Area | North America |
| Toxicity | Toxic to humans, Toxic to pets |
Oakleaf Hydrangea Care
When the plant is dormant and won’t be affected by extreme heat, plant fresh oakleaf hydrangea in the late fall or early spring. Planting this shrub in full sun or partial shade with rich, well-draining soil that leans slightly acidic will yield the greatest results. It prefers damp soil, therefore covering the root zone with a thick layer of mulch will help keep the soil moist.
Light Requirements
Since oakleaf hydrangeas are understory plants in their natural habitat, midday shade is beneficial to them, especially in southern climes where nearly full shadow may be required. Oakleaf hydrangeas can survive in full light in the North. Excessive shade could lessen the fall color’s brilliance.
Soil & Potting
Grow oakleaf hydrangea on well-drained soil that has been amended with lots of compost to bring the pH of the soil down to 5.0–6.5.
Watering
These plants prefer moist soil, and their water requirements increase with the amount of sunlight they receive. Maintaining soil moisture can be aided by covering the ground beneath the shrub with a thick layer of mulch.
Temperature and Environment
All over its hardiness range (zones 5 to 9), oakleaf hydrangeas thrive in temperate conditions; but, in the colder regions of their range, winter damage to flower buds may occur, especially with young shrubs.
Fertilization
Generally speaking, this plant doesn’t need to be fed, especially if the root zone is mulched. Growing in alkaline soils may benefit from sporadic application of an acid fertilizer.
Oakleaf Hydrangea Varieties
‘Snow Queen’:Â ‘Snow Queen’ is a well-liked cultivar of oakleaf hydrangea that blooms in early summer in panicles of white flowers that progressively turn pinkish-brown in the fall. The flower arrangement lasts a very long time.
‘Snowflake’:Â Some growers like this cultivar because of its double blossoms.
‘Ruby Slippers’: This cultivar stays more compact at 3 to 4 feet tall and wide, making it maybe more suited for small-space gardening enthusiasts. As suggested by the cultivar name, ‘Ruby Slippers’ flowers mature to a ruby hue.
Pruning Oakleaf Hydrangea
Shrubs containing oakleaf hydrangeas tend to spread widely, sometimes irregularly, with branches pointing in all directions. You can maintain the shape and health of your hydrangea by pruning it annually or by cutting back any overgrown branches every two years. Under perfect circumstances, this plant could grow up to ten feet, so you might need to prune it. Pruning should wait until after flowering, when blossoms start to fade, usually late August into September or even October, as it blooms on old wood. When branches become sick or damaged, they might be removed.
Since this plant expands by suckers, you might wish to cut off ground sprouts that are spreading in order to stop the shrub from getting too big.
Propagating Oakleaf Hydrangea
Stem cuttings are a successful method of propagating oakleaf hydrangea bushes. Adhere to these propagation guidelines:
- Take two to four cuttings from green stem tips devoid of blooms using clean, sharp pruners. Verify if the cuttings have one or more growth nodes, which are shown by a knobby line across the stem.
- Take off the leaves from the cutting’s lowest portion.
- Insert the cutting end into the rooting hormone.
- Sow the cuttings in sterile, damp potting soil.
- The planted cuttings should be kept out of direct sunlight and placed in a plastic bag.
- Ensure that the soil stays damp but not drenched.
- The plant should be able to be transplanted into the garden or a larger pot for continuing growth after about 12 weeks of root growth.
How to Grow Oakleaf Hydrangea From Seed?
‘Snow Queen’ is a popular cultivar; however, propagating it from seed does not yield true-to-type plants. Therefore, it is advised to propagate it using the previously mentioned stem cuttings.
Overwintering
In zone 5, which is the northernmost point of its hardiness range, young plants need to be protected from the winter elements with something like burlap wrap.
Common Pests & Plant Diseases
The oakleaf hydrangea is not severely affected by pests or diseases, although it can have leaf blight or powdery mildew. Aphids may also occasionally surface.
How to Get Oakleaf Hydrangea to Bloom?
Numerous factors can prevent a bloom from occurring. The bush may not receive enough sunshine. Although they enjoy dappled shade, hydrangeas require sunlight in order to bloom. Another reason could be a shortage of water. To keep the soil from drying out, keep it damp and cover it with a thick layer of mulch.
Steer clear of nitrogen-rich fertilizers, as they produce luxuriant foliage but no blooms. Make the switch to a high-phosphorus (P) fertilizer that promotes blooms.
Pruning should be done carefully to prevent damaging flowerbuds, which can easily be damaged by a late spring freeze.
Your hydrangea may be too young if you have tried all of those remedies and it is still not blooming. Keep up the good work and cross your fingers for a blooming season the next year.
Also Read: Larkspur (Delphinium) Complete Guide To Grow And Care
