Gardening expert warns which plants to keep 'far away' from hydrangeas

Hydrangeas, with their large and vibrant blooms, are a favourite among garden enthusiasts.

There's a variety of plants that pair nicely with hydrangeas. Perennials, shrubs, and annuals such as hostas, gardenias, ferns, hollies, yews, azaleas, and boxwoods are recommended as companion plants for hydrangeas.

However, certain plants can be detrimental to the beautiful blooms, stunting their growth or even leading to their demise.

READ MORE: Gardening expert shares easy way to boost hydrangea flowers

To prevent gardeners from planting hydrangeas near potentially harmful plants, gardening expert Julia Omelchenko from Plantum has offered her guidance.

She advised: "Hydrangeas are beautiful and popular garden plants that, when properly cared for, can be a sight to behold thanks to their large inflorescences. However, sometimes they may be weak, fail to bloom, and experience wilting and leaf dieback even in proper growing conditions. The problem might lie in the neighbouring plants in your garden.", reports the Express.

1. Trees

It's not recommended to plant hydrangeas where they will be deprived of sunlight, hence tall trees are a definite no-go for these flowers.

The expert elaborated: "Tall and large trees like the oak, maple, or birch can provide too much shade for hydrangeas, making it difficult for them to flower."

"Hydrangeas prefer bright but diffused sunlight, and too much shade can cause stunted growth. If there isn't enough light, the plant won't bloom or its inflorescences will be small and weak."

Additionally, large trees and Hydrangeas compete for nutrients in the soil. This can lead to nutrient deficiency, which will also "negatively affect" the development of hydrangeas.

2. Plants that release juglone

Some plants produce substances that inhibit or suppress the development of other plant species - this is known as allelopathy.

Julia pointed out that "walnuts are a particular threat to hydrangeas" because they can release a toxic compound called juglone into the soil. The expert stated: "Juglone negatively affects the development of hydrangeas and other plants, causing their leaves to turn yellow, shoots to wither and dry out, and the plant to die."

If gardeners have walnut trees on their property, Julie advised: "Plant hydrangeas as far away from them as possible".

3. Lavender

Loved by many gardeners, lavender is another plant that isn't a suitable neighbour for hydrangeas. Although they can look beautiful together, they have opposite growing requirements, and planting them next to each other can "cause problems for both plants" so they should "never" be planted beside one another.

Lavender prefers dry, well-drained, and not overly nutritious soil, whereas hydrangeas need moist, fertile, and slightly acidic soil.

Julius cautioned: "If you plant these two next to each other, you may have difficulty providing optimum growing conditions for both of them. Wet soil, which is essential for hydrangeas, can cause the lavender's root system to rot, as it cannot tolerate excess moisture.

"On the other hand, dry and poor soil preferred for the lavender can cause chlorosis and drying out of hydrangea leaves because they won't get enough moisture and nutrients needed for growth and development."

4. Sun-loving plants

Hydrangeas prefer places with bright but diffused light, long periods of exposure to direct sunlight can cause their leaves to turn yellow, brown, and dry out, which "can later cause the plants to die".

Julia pointed out that sun-loving plants like roses, asters, and geraniums are "undesirable neighbours" for hydrangeas due to the different light conditions required for their growth.

Another plant worth mentioning is the sunflower, which not only needs a lot of direct sun but also absorbs all the nutrients from the soil, depleting it.

This results in stunted growth of nearby plants, which may include hydrangeas. Instead, hydrangeas are best planted alongside other plants which prefer diffused sunlight.