A Complete Guide to Hydrangea Care

Hydrangeas are a truly beautiful addition to any garden and are not difficult to grow. These sunshine and water-loving plants are fairly hardy, and with a little care will provide year after year of magnificent colorful flowers. 

How to grow the perfect hydrangea

Here at French Florist, we use the stunning hydrangea bloom to add color, texture, and a dash of splendor to our bouquets. Use our quick guide to growing the perfect hydrangea, and be rewarded with spectacular blooms to cut, or enjoy outside.

Pruning hydrangeas

Knowing when to prune a hydrangea plant depends largely upon the variety being grown. Some hydrangea varieties, such as Hydrangea Paniculata and Hydrangea Arborescens, will flower on new growth, while others such as Hydrangea Macrophylla and Hydrangea Serrata develop blooms on the plant’s ‘old wood’; its growth from the previous year. If you’re not sure which variety of hydrangea you have, observe its growth pattern for the first year to see where the new flower buds form. 

Deadheading hydrangeas

Hydrangeas that flower on new growth will rebloom after being deadheaded, and their spent blooms can be removed throughout the blooming season to promote new growth. Those that flower from buds that have developed on old wood will bloom only once. 

Deadhead when the blooms on your hydrangeas turn brown and dry, removing the flower head just above the first set of leaves. Take care not to cut off next year’s flower buds when these begin to show, usually towards the end of the summer. 

In colder climates where winter frosts are common, spent blooms on hydrangeas that flower from new growth can provide useful protective insulation to the plant’s stems through the winter months. They can then be deadheaded in the spring. The spent hydrangea bloom can even make an attractive addition to a dried flower arrangement.

Controlling hydrangeas color

One of the appealing features of Hydrangea Macrophylla and Hydrangea Serrata is their ability to flower in different colors depending upon the pH and phosphorus levels of the soil in which they are planted. With a little know-how, you can determine whether a hydrangea grows pink, blue or purple. With a little alchemy (aluminum sulfite, to be precise), blooms can be changed to blue, and to achieve pinker blooms use garden lime. 

Hydrangea placement

The location of a hydrangea plant in your garden will affect how well it grows as well as the overall shape of the plant. Those plants placed in too shady a location may suffer from spindly or “leggy” growth, where stems have grown too long in an effort to reach sunnier space, aside from climbing varieties which can manage in shadier spots. While they like the sun, hydrangeas are thirsty plants, so the full sun can mean a lot of water to prevent soil from becoming too dry. They do best in dappled shade, where the sun is available but soil stays moist for longer.

Growing hydrangeas in containers

Container-grown hydrangeas are usually quite happy and allow you to relocate your plants easily. They can even manage indoors if placed in enough sunlight and watered regularly. To give your container-grown hydrangea the best chance of success, ensure its container is large enough that the soil doesn’t dry out too quickly, and that it has drainage holes, to avoid root rot. Water your plant thoroughly enough that the soil remains slightly moist. 
Prune as required for the size of the container, or choose a dwarf variety.

Soil

Being water-loving, hydrangeas will grow well in most types of soil, including clay-based and compacted soils if there is sufficient drainage. They thrive, however, in friable (more crumbly) soil, and no fertilizer will be needed if the soil is fairly nutrient-rich with organic content. They are happy in multipurpose or ericaceous compost and their color will be affected by the type of soil in which they are grown.

Temperature and humidity

Hydrangeas enjoy humidity but will be just fine in drier climates if watered regularly. Being hardy plants, hydrangeas are happy in a range of temperatures - particularly, for new-growth plants, if they’re pruned correctly. These plants will overwinter successfully in Department of Agriculture plant hardiness zones 3 through 8, but there are some varieties that may require cold-weather protection. 
Hydrangeas from florists tend to be a little less hardy than nursery-grown plants and may need some protection in winter or early spring, such as insulation with a layer of leaves using a wire screen surrounding the plant, or a lightweight paper or fabric wrap to ward off frost. 

When do hydrangeas bloom?

The hydrangea blooming season is dependent upon the variety and the planting zone. Most new growth hydrangeas bloom in spring, summer and early fall, however, in hotter climates, these plants may continue to flower later into the fall after taking a slight break from blooming in the hottest part of the summer.

What are some common hydrangea problems?

While hydrangeas are fairly straightforward to grow and maintain if looked after properly, occasionally problems arise which mean your flowers or leaves do not look their best. Often these can be easily remedied with a little knowledge about what might be causing their lackluster appearance.

No blooms

A hydrangea that doesn’t flower, or flowers poorly, may be suffering as a result of incorrect pruning, for example, if the following year’s buds are accidentally removed during deadheading or cutting back. Buds may also be affected if the plant is a less hardy type and isn’t protected from cold and frost. Flowers can also suffer as a result of fertilizer overuse, lack of sun, too much moisture (undrained container or soil), or due to transplant shock if moving the plant to a new location. 

Drooping leaves

A hydrangea that is drooping may be suffering from too much fertilizer, resulting in too-nitrogen-rich soil, or simply because of incorrect watering and plant location. Restore a droopy-leafed hydrangea back to its former glory by ensuring it is watered regularly and isn’t in too sunny a spot in the garden.

Yellowing leaves

Yellowing leaves are usually a sign of “wet feet”, that is, the plant becoming waterlogged. This can be easily remedied by ensuring your plant is in soil - or a container - that allows effective water drainage.

Other possible causes of yellowing leaves are fungal diseases, a lack of iron, or a lack of nitrogen. Again, this problem can be quite easily remedied by feeding the plant Epsom salt and nitrogen-rich fertilizer - although not too much that its leaves begin to droop! Observe your hydrangea’s behavior to determine the optimum nitrogen levels for the plant in your garden or container.

Buy beautiful hydrangeas online with French Florist for same-day local delivery.