Blooming in summer and spring, hydrangeas are truly stunning and nothing less than show-stoppers. Their beautiful flower heads grow in a wide variety of shapes, from cones to large balls, and bloom in numerous shades of blue, pink, and white. While they may seem like an incredibly high-maintenance plant, they’re actually pretty easy to grow. So, when’s the best time to plant hydrangeas?
It’s best to plant hydrangeas during fall or spring in moist, well-drained soil. If you’re growing them in pots, start the process in April or May, and keep them in a sheltered spot. Cover them during winter, and remember that it can take up to four years for hydrangeas to reach their full size.
Like most flowers and vegetables in your garden, knowing the basics of planting hydrangeas can help save you both time and money. By achieving the right soil pH balance, picking the ideal location, and planting properly, you’ll be able to enjoy large, vibrant hydrangeas for years to come. Let’s look at the best time to plant hydrangeas, how you can plant and grow the flowers, and which species to start with.
Which Month Is Best for Planting Hydrangeas?
While you can plant hydrangeas throughout the year, it’s best to get them into the ground in fall or spring when the soil is moist and the weather is mild. You can start the planting process in summer as well, but just make sure you keep an eye on the soil’s moisture levels.
The idea is to give the flowers enough time to develop a healthy and sturdy root system before they start to bloom. It’s advisable to plant hydrangeas in the late afternoon or early morning, so they’re protected from the intense midday heat.
Planting Hydrangeas in Pots
It’s better to plant small shrubby hydrangeas, like Little Lime, in pots or containers during the months of April and May. You can also plant them in other months, but try to avoid those that are extremely cold or extremely hot.
Pick a good pot with proper drainage holes and add a mix of John Innes No. 3 compost and organic peat-free compost into it. Place the pot in a sheltered area, and always keep the compost moist, but not so much so that it becomes waterlogged.
Also, if you want to grow vibrant, blue hydrangeas, but don’t have acidic soil, you can simply plant them in pots of ericaceous compost.
Planting Climbing Hydrangeas
You can plant these self-clinging climbers at any time of the year, as long as the soil is not frozen, waterlogged, or parched. However, keep in mind that planting them in fall or spring will yield the best results.
Climbing hydrangeas can take a long time to grow, but they’re so long-lived and stunning that the wait ultimately becomes worth it.
How to Plant Hydrangeas
In order to plant hydrangeas, you first need to dig a large, wide hole into the ground. Make sure the hole is just as deep as the root ball and at least two feet wider than the roots.
Water the plant thoroughly and add mulch to the area surrounding the plant to keep the soil properly damp and moist.
Where’s the Best Place to Plant Hydrangeas?
The basics of proper hydrangea care are exactly the same whether you plant them in pots or directly into the ground. Most people grow hydrangeas in their garden, but some species thrive just as well in pots.
To help you decide where to plant them, here’s a more detailed explanation:
Growing Hydrangeas in the Garden
A lot of people plant their hydrangeas in flower beds next to their fences or homes. This is because the plant loves the warm morning sunlight but isn’t a fan of the intense heat of the afternoon.
If you’re planting your hydrangeas in the garden, it’s better to plant them in a sheltered area where the flowers can enjoy sunny mornings and cool afternoons. They also thrive in moist, well-drained soil, so try to avoid placing them in south-facing locations, especially if the soil is dry.
If you have an extremely shaded spot, like a north-facing wall, you can plant climbing hydrangeas alongside it. However, the young growth is susceptible to frost damage during spring, so avoid placing them in a frost pocket. It’s also best to plant them in an area that’s protected from strong winds, so the flowers and leaves won’t get damaged.
Hydrangea plants thrive in almost all soil types, including acidic and alkaline soil. However, the soil’s pH will affect the color of the flowers of certain species. For example, some hydrangeas that usually bloom pink appear blue in acidic soil.
Don’t plant hydrangeas directly underneath trees, as this can lead to a competition for nutrients and water. It’s also advisable to know the size of a mature shrub before picking a spot, so you can provide it with enough space to grow to its full size.
Growing Hydrangeas in Pots
You can easily plant hydrangeas in pots, as long as you pick the correct species. It’s better to plant dwarf hydrangeas, such as ‘Little Lime’ or ‘Mini-Penny’ in containers. However, make sure that the pot is large, has proper drainage holes, and contains a high-quality container potting mix (on Amazon).
How to Grow Hydrangeas
For the most part, growing hydrangeas is quite easy. However, there are a few specific requirements you’ll need to meet to make them thrive. Here are some detailed growing instructions that can help achieve the best results:
Soil Conditions
Hydrangeas thrive in well-drained soil that’s rich in organic matter. Avoid planting them in soil that’s too sandy or light and can’t hold moisture. However, keep in mind that you can improve the drainage and moisture retention of poor-quality soils by adding worm castings or compost.
Don’t plant the flowers in an area that frequently holds standing water. This is because saturated soil leads to root rot and makes your hydrangeas more vulnerable to fungal disease.
Some species are also incredibly sensitive to the pH balance of the soil. In fact, you can change the color of certain flowers by altering the acidity levels. The flowers on ‘Invincibelle Spirit II’ and ‘Endless Summer’ will bloom in shades of blue in extremely acidic soils, purple in slightly acidic ones, and pink in alkaline soils.
If you’re uncertain about your soil’s pH level, you can simply use a soil tester (on Amazon) to find out.
Fertilizer
Once their root system is established, it’s not necessary to fertilize hydrangeas regularly. However, if you’ve planted them in low-quality soils, it’s better to feed them once a month for the best, most vibrant blooms.
Add a fertilizer that has a high phosphorus content to promote healthy blooming. You can also add granules to the soil at planting time and then top dress it monthly throughout the summer.
Water-soluble plant feed is a good option as well. You can feed your hydrangeas with liquid fertilizer whenever you water them or add compost tea and fish emulsion to ensure a strong, healthy root system.
If you have alkaline soil, you can change the color of the flowers on species that are highly sensitive to soil pH levels. You can either use a water-soluble fertilizer every time you water your plants or a granular acidic fertilizer once a month to achieve the color you want.
Disease Control
While powdery mildew affects all hydrangea varieties, the Bigleaf types are more susceptible to the fungal disease. It only affects the look of the flowers and does not damage the plant’s overall health, so it’s not necessary to add chemical fungicides.
Instead, you can opt for more preventative measures, such as removing any spent debris and leaves after the growing season.
Also, it’s important to note that poorly drained soil can lead to root rot. Choose a site with proper drainage and make sure you don’t over-water the plant.
Pest Control
Healthy hydrangeas are less likely to have pest infestations. While aphids love new hydrangea growth, they’re quite easy to control and prevent.
If you notice an aphid problem in your plants, just spray the shrub with neem oil or organic insecticidal soap (on Amazon). Treat your hydrangeas regularly until the bugs are gone completely.
Pruning Hydrangeas
Pruning your hydrangeas can help increase the size and improve the shape of the bloom. But before you start, it’s important to know whether the plant flowers on old or new growth. This will help determine the right time to prune.
Generally, flowers that grow on old wood bloom during the spring and fade back in midsummer. It’s better to prune these species after they’ve flowered.
On the other hand, plants that flower on new growth bloom from late summer to fall. You should prune them in late fall after the shrub becomes dormant, or at the beginning of spring before they come out of dormancy.
Do Hydrangeas Like Sun or Shade?
Hydrangeas can’t tolerate full shade or full sun. They thrive on an east or north wall, or any spot that receives partial sun.
In northern, colder climates, they can withstand a bit more sun. If you live in a warmer climate, you’ll need to plant your hydrangeas in a location that receives more shade. However, keep in mind that too much shade can lead to fewer and smaller blooms.
Conversely, too much sun can result in dull and wilted foliage and can turn the flowers brown very quickly.
Do Hydrangeas Like Lots of Water?
Giving your hydrangeas the right amount of water is one of the most important elements of successful plant care. Make sure you water them consistently, especially during the first couple of growing seasons.
If you under-water your hydrangeas, their leaves will start to wilt. Make sure you provide them with at least one inch of water every week.
If your area is suffering from droughts or extreme summer heat, it might become necessary to water the shrubs daily. If you’re still uncertain about the correct amount of water, you can use a simple moisture meter to make the task easy.
How Long Does It Take for a Hydrangea to Grow to Full Size?
The answer to this question depends on the type of hydrangeas and the planting zone you’re living in. A lot of new growth hydrangeas grow buds in the early summer and bloom in the following summer, spring, or early fall seasons.
In warmer climates, hydrangeas might stop blooming in the intense summer heat but will bloom again in the fall.
While they’re fast-growing plants, it usually takes around two to four years for hydrangeas to grow to their full size. However, keep in mind that some types mature faster than others.
Which Hydrangeas Are the Easiest to Grow?
If you’re a novice gardener, then it’s better to start with a few oakleaf varieties. Oakleaf hydrangeas can withstand droughts, handle more sun, and tolerate colder weather.
They’re also more resistant to pests and diseases and grow better in sandy soil compared to other hydrangeas. However, keep in mind that all oakleaf hydrangeas are white, so you might have to plant other flowers to add a bit of color to your garden.
Here are a few hydrangeas that are extremely easy to grow:
Alice Hydrangea
These big and beautiful flowers are often considered the most trouble-free and robust hydrangeas you can grow. However, keep in mind that they have a 15-foot spread and can grow up to 15 feet tall.
They flower in the months of June and July and develop large, cone-shaped blooms that later fade to pink. They have beautiful bronze and burgundy fall foliage and are somewhat deer-resistant as well.
- Type: Oakleaf
- Sunlight: Full-partial sun
- Shrub Type: Deciduous
- USDA Hardiness zone: 5 – 9
- Soil: No specific soil pH or soil type
Snowflake Hydrangea
These hydrangeas have an extremely long bloom time, starting from June and going up to late summer. They get their name from their stark white, double blossom flowers (that predictably resemble snowflakes), while their deep maroon foliage further adds a beautiful, eye-catching contrast.
It’s important to note that snowflake hydrangeas are a fast-growing species, and their blooms fade to pink before completely turning brown.
- Type: Oakleaf
- Sunlight: Partial sun, but they can also survive in full sun if you water them often.
- Shrub Type: Deciduous
- USDA Hardiness Zone: 5 – 9
- Soil: Moist, rich soil
Ruby Slippers Hydrangea
Growing up to only four feet, this tiny plant boasts lovely, nine-inch hydrangeas. The giant, white flowers bloom in early-mid summer but quickly adopt a more vibrant, rosy color. They also have bright, crimson fall foliage that lasts until early winter, while the blooms themselves last for up to two months.
Ruby slippers hydrangeas thrive in droughts, poor soil, and heat as well, so you can easily plant them to brighten up even the smallest gardens.
- Type: Oakleaf
- Sunlight: Full-part sun
- Shrub Type: Deciduous
- USDA Hardiness Zone: 5 – 9
- Soil: Rich, well-drained soil
Do Hydrangeas Need to Be Covered in Winter?
The answer to this question depends on how low the temperatures drop during winters in your area. If the temperature stays above 0˚F (zone 7), then there’s no need to cover your hydrangeas.
However, if the temperature drops below 0˚F, then you should completely cover or wrap marginally hardy plants. This is particularly important for species that grow on old wood, like Bigleaf or mophead hydrangeas.
But the good news is that newer varieties of Bigleaf/mop head hydrangeas bloom on both old and new wood, so you don’t need to worry too much.
Generally, hardier species, like the arborescens and paniculata, don’t need any additional winter protection, but extremely cold winds can cause the branches to die back. If you’re expecting a colder than normal winter, then it’s better to cover hydrangeas.
You can loosely wrap the plants with a few layers of burlap and secure them tightly with a sturdy wire. If you have smaller, newly planted hydrangeas, you can cover them with a mulch mountain.
Additional Tips for Winter Care
While most hydrangea plants are considered hardy, extreme weather can throw them for a bit of a loop. You’ll need to give them some extra attention, so they can survive the winter and grow back bigger and better next season.
Don’t Stop Watering
Make sure you water hydrangeas until the soil freezes solid. It’s important to water them consistently and deeply since they’re thirsty shrubs by nature.
If you live in a warmer climate where you don’t have to worry about the ground freezing in the winter, water your hydrangeas deeply but sporadically throughout the season. Make sure you adjust the amount of water according to the amount of rainfall you receive.
It’s advisable to fill a five-gallon bucket with water, cut out a small hole from the side, and set it near the base of your plants, so the water trickles out slowly. You can also turn on your garden hose to a very slow trickle and place it at the base of your hydrangeas for around an hour or so.
Add Compost
Feeding your hydrangeas one last hearty meal can help give them a boost for the next flowering season. In colder climates, top dress your plants with well-aged manure or compost before covering them with mulch.
On the other hand, if you live in a warmer region, then it’s better to add compost in early winter or late fall.