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Annabelle Hydrangea Care Guide

Annabelle hydrangeas have become essential in gardens everywhere. They add a lovely touch to any outdoor space with their big white blooms.

These hydrangeas are part of the Hydrangea arborescens species, also known as Smooth hydrangea, native to the USA. They’re easier to care for compared to Bigleaf hydrangeas.

For best growth, plant ‘Annabelle’ in moist, well-drained soil, and place them where they get either full sun or partial shade. Although they’re quite hardy, beware of late frosts, as they can harm the buds. A sheltered spot or near a warm wall can help in cooler areas. Prune them regularly to keep the plants looking full and tidy.

Annabelle Hydrangea Care

Annabelle Hydrangea

Plant profile:

Annabelle Hydrangea Care instructions
Hardiness: USDA zone 3-9
Size: Height 3-5′ and width 4-6′
Shape: Rounded with upright stems.
Type: Perennial, deciduous, shrub.
Light requirements: Full sun and partial shade.
Soil: Loam or amended soil.
Soil pH: 5.5-7.0 Grow best in slightly acidic to neutral soil.
Watering: 1-2 times per week in drought. Don’t water in the winter.
Growth rate: Fast
Blooming: June-September. On new wood.
Flowers color: White, light-green, pink.
Leaves: Dark green, 3-8 inches long.
Fragrance: Low scent.
Best time for planting: Early spring and early fall.
Pruning: Pruning can be done at any time of year, except for pruning new wood before flowering.
Reblooming: Rarely.
Spacing: 3-4 feet apart (center to center).
Transplanting: Early spring.
Winter care: In 4-5 zones can die back for the winter.
Spring care: Clean the hydrangea and remove all the deadwood.
Fall care: Keep the soil around it slightly moist. Avoid the use of fertilizer. Remove all deadwood and fallen leaves.
Fertilizer: Balanced NPK formula, once per year in early spring.
Propagation: By cuttings in early spring.
Deer resistant: No
Problems: Pests, diseases.

Planting

The ideal times to plant Annabelle hydrangeas are in early spring or fall. Planting in spring, when the plant is still dormant, helps it adjust better to new surroundings.

Choose a sunny spot with ample moisture for your Annabelle hydrangeas. Make sure to keep a distance of about 2 feet from your house, and space them 3-4 feet apart from other plants.

When planting, dig a hole that’s twice the size of the plant’s root ball. Partly fill it with improved soil, then place the hydrangea in the middle. Surround the roots with this soil, pressing it down lightly. Be careful not to cover the stems or the point where they meet the roots with soil.

Sunlight

Light requirements

Annabelle hydrangea in semi shade.

Annabelle hydrangeas flourish with lots of sunlight, which helps them produce their large white flower clusters. They need at least 6 hours of direct sunlight each day, though 8 hours is even better.

These hydrangeas can handle full sun without much trouble. However, it’s crucial to water them regularly in such conditions because they lose more moisture in full sun compared to shade. Also, when planted in full sun, it’s a good idea to mulch around the hydrangeas to keep the soil from drying out.

On the other hand, Annabelle hydrangeas don’t do well in full shade. Without enough light, their stems become weak, and they either won’t bloom at all or will produce very few flowers.

Soil

Annabelle hydrangea care

Annabelle hydrangea with green flowers.

Annabelle hydrangeas can adapt to various soil types, but they struggle in heavy clay soil. Dense clay makes it tough for roots to grow and can cause water to stagnate, leading to root rot.

If your soil is too clayey or sandy, you’ll need to enhance it for Annabelle hydrangeas to prosper. Using compost is a great solution. Opt for compost from reputable sources to ensure it’s free of diseases and pests.

When planting, add a couple of buckets of compost to the hole and mix it well. This soil preparation will support healthy hydrangea growth for years to come.

The ideal pH level for Annabelle hydrangeas is between 5.5 and 7.0. They thrive in slightly acidic to neutral soil, which aids in nutrient absorption. Avoid planting in alkaline soil, as it can cause chlorosis, a condition where leaves turn yellow.

It’s worth noting that soil pH doesn’t change the color of Annabelle hydrangea flowers like it can with Bigleaf hydrangeas.

Watering

Water your Annabelle hydrangea once or twice a week, unless it’s raining. If there’s even a bit of rain, you can skip watering.

Always check the soil around your hydrangea for dryness. If the top 1-2 inches of soil feel dry, it’s time to water. Generally, 2-3 gallons per plant should be enough to keep it sufficiently moist.

Be cautious of overwatering, a common issue with Annabelle hydrangeas. Overwatering can turn the leaves yellow. To prevent this, let the soil dry out slightly, about 1-2 inches deep, between waterings. Using well-drained soil and ensuring proper drainage will help.

In extremely hot weather, Annabelle hydrangeas might drop their leaves if they don’t get enough water. If you notice this, water the plant immediately, and it should recover quickly.

Pruning

Annabelle hydrangea care

Annabelle hydrangea fall over.

Trimming Annabelle hydrangeas isn’t necessary, but you can prune them almost any time of the year. Since they bloom on new wood, avoid cutting new spring stems.

When pruning, cut the stems back to about 10 to 15 inches above ground level. Leave these short stem sections sticking out; they’ll support next year’s growth and help the hydrangea maintain its shape.

Deadheading the hydrangea after it blooms is beneficial. This practice encourages larger blooms the following season.

Always use sharp and clean tools for pruning. When deadheading, cut close to the flower head to avoid harming the next year’s buds.

Transplanting

Annabelle hydrangea care

Newly planted Annabelle hydrangeas.

The ideal time to move an Annabelle hydrangea is early spring, before the leaves start to open. It’s best to do this on a cloudy day to avoid direct sunlight. Water the hydrangea well a few days before you plan to transplant it.

Carefully dig up the hydrangea, trying not to damage any roots. The less root damage, the quicker the hydrangea will adapt to its new location. Keeping as many roots intact as possible is key.

When moving the plant to its new spot, keep the soil around the roots. Place the root ball in the new planting hole and fill it with well-drained soil.

If the Annabelle hydrangea starts to unfurl its leaves, provide some shade using a mesh for the first few weeks. Keep the soil moderately moist and don’t forget to mulch around the plant.

Winter care

Winter

Annabelle hydrangea in winter.

To help Annabelle’s hydrangea get through winter, start by cleaning up in the fall. Remove any fallen leaves from under the bush to prevent rot and diseases.

Then, add a layer of fresh, well-prepared compost as mulch. If fall is dry, water the hydrangea just enough. This helps it hold onto moisture during winter.

In colder areas, Annabelle hydrangea might not survive the winter. You have a few options: protect it during winter, leave it as is (it’ll grow back and bloom in spring), or trim it down to 10-15 inches above ground to prevent dying back.

Fertilizer

For Annabelle hydrangea, a balanced slow-release fertilizer works best. Look for one with equal amounts of Nitrogen, Phosphorus, and Potassium. This blend provides all the necessary nutrients steadily over the growing season.

Fertilize Annabelle in early spring. This timing helps the plant grow strong leaves and big flowers.

Generally, one application of fertilizer is enough. Over-fertilizing can make the plant grow too much, making it weak. Also, too much fertilizer can make the hydrangea more prone to diseases.

Problems

Leaf tier

Leaf tier twisted Annabelle hydrangea leaves.

Annabelle hydrangea isn’t deer-proof. Deer can munch on the leaves and make the plant look bad. If deer visit your yard, consider using a deer repellant or fencing around your hydrangeas.

Pests can also be a problem for Annabelle hydrangeas. Aphids, spider mites, thrips, and other insects like to eat the sap and leaves. If you spot these pests, treat the plant with garden oil. For mites, acaricides are effective.

Diseases often show up as leaf spots on Annabelle hydrangeas. Treating the leaves with a fungicide can help. Also, ensure there’s good air circulation around the plant.

Yellow leaves can be a sign of overwatering. To prevent this, use well-draining soil and let the soil surface dry out between waterings.

If Annabelle’s leaves wilt, it might be due to too much sun or not enough water. In such cases, move the plant to a partially shaded spot and water it more frequently.

Propagation

To propagate Annabelle hydrangea, use cuttings. In early spring, before the leaves appear, cut 4 to 6-inch pieces with several nodes.

Fill pots (at least 4 inches wide and with drainage holes) with sterile seedling soil. Plant the cuttings in the soil so that one-third is buried and two-thirds sticks out. Water the soil thoroughly and then place the pots in a greenhouse. Rooting might take a few months.