How to Grow Hydrangeas in Full Sun

Hydrangeas can thrive in full sun for as long as they are planted in soil that is able to hold onto moisture. They also receive regular mulching to hold the water. Different varieties of the species Hydrangea paniculatahave been developed to thrive extremely well in full sun and produce a stunning display of flowers.

In full sun, hydrangeas require up to 2 gallons of water per day, even during the hottest days of summer.

There are some specific best practices to grow the hydrangeas in full sun that you must adhere to in order to reap the most benefits of your Hydrangea.

Read on to discover whether you have to make any changes to your garden in order to plant stunning hydrangeas in full sunshine.

1. Moisture Retaining Soil for Hydrangeas in Full Sun

If you’re fortunate that you have garden or loam soil with lots of organic matter, it’s the perfect soil for most plants, including the hydrangeas which are in full sun.

If you’ve got soil that is sandy or does not receive any mulch, the soil won’t retain the required water, hold sufficient nutrients, and drain too fast to cultivate the hydrangea.

The majority of sunny gardens will require to amend their soil prior to planting hydrangeas to maintain the proper balance of moisture and to ensure it is ensures that your soil is not too loose to allow those hydrangea’s roots will grow nice and deep and increase their resistance to drought.

The most organic substances for amending your soil with to hold enough moisture to allow hydrangeas to flourish are:

  • Leaf mold
  • Compost (garden compost is typically more effective, but commercial compost can be effective)
  • Manure that has been well rotted

Each of these organic substances have a remarkable capacity to absorb water, yet the structure of their materials is flexible (loose) to ensure that excess water won’t clog root systems of hydrangeas which can cause turn brown.

Moist soil doesn’t necessarily mean wet soil, so if you have clay that is heavy in your garden, you must to make sure that the soil isn’t flooded for long time after rainfall. A well-drained, moist soil is vital.

blue and white flowering hydrangea in sun

Amending Soil for Sunny Hydrangeas

The roots of Hydrangeas are quite small and develop to a minimum of about 6 inches at maturity, but they are known to spread their roots wide.

This means that you’ll need to incorporate organic matter like leaves or compost in to a depth of six inches before you plant.

In terms of width , you must amend the area to be approximately three times the size of the pot from which you purchased your hydrangea, so that the roots expand out and benefit from the newly amended moist soil.

The more dry your soil naturally the more leaves or compost you’ll require to add. For sandy soils, this could require replacing all soil around the plant with compost.

I would suggest heaping the compost you want to use on the soil and then digging up all the soil to the desired depth using a fork and spade. If you own one, you could use tillers that do well at mixing the compost amendment in the soil in a uniform manner and saving on labor!

After you have planted and watered your hydrangeas in the new soil, it is essential to apply a layer of mulch on the soil to reduce the rate of the loss of water and to help keep it in place. It is essential to apply mulch on hydrangeas that are in sunny areas frequently.

Scroll down to tip 4, for tips on the best mulch to use for the hydrangeas…

2. Select an Hydrangea that is suited to the full Sun

Hydrangeas of this variety of Hydrangea paniculataare most suited to the full sunlight or early morning sunlight and shading in afternoon.

It is a plant species that grows natural habitats in South China, Japan Korea and Japan Korea. It has been grown to produce a range of colors with stunning flowers in a variety of shades of pink, white and green. It can be found in a variety of sizes.

“Silver Dollar”, “Pink Diamond and ‘limelight’ are the most popular varieties with excellent examples available online.

But I would suggest going to the nearest garden store and looking through their selection during the summer months to understand the size, color and scent of the flowers from the hydrangea. You can then decide which one is suitable to your yard.

3. Watering Hydrangeas in Full Sun (use a Beaded Hose)

Hydrangeas are thirsty plants that prefer humid (but but not wet) soil. Therefore, an effective watering schedule is vital.

Hydrangeas in full sun during the hottest days will require watering each day. However, if there are clouds and cooler temperatures, you might only require watering once every two or three days.

It is essential to check the moisture levels of the soil before deciding whether or not to soak the soil. When the soil appears only slightly damp or dry to the point of a finger then your hydrangea is likely to require an ample soak.

If the soil is dry and cool to a finger’s depth, then you may not water for a few days.

Hydrangeas should be watered early in the morning to ensure that it’s hydrated throughout the day, even in hot and sunny weather and that the soil stays wet in the hottest time during the day.

The amount of water your need for your hydrangea will be determined by how big the plant is. The larger the hydrangea, the more water it’ll require. I recommend that watering the hydrangea by at least 2 Gallons (7 7 litres) of water during warm days.

The water should be drained slowly, to give the water the chance to soak into the soil, and not flow off the surface.

This method of watering keeps the soil moist to an adequate depth, which encourages roots to develop deeper and, consequently, be less prone to the dry effects that the sun can cause.

If your garden is a particularly sun-filled garden, I suggest to invest in an soaker (drip line) irrigation hose.

The water will gradually release into the soil at a pace that will allow it to soak into and help keep the soil moist throughout an extremely hot day (without over-saturating the soil). The hoses can be left in place for a few days during the hottest weather to make sure you are meeting the requirements for water in the Hydrangea.

An irrigation system can help you save a lot of labor in the process of watering , and will create ideal conditions for all types of plants that are in full sun.

4. Mulch Hydrangeas Regularly (Helps Retain Moisture)

It is essential to apply mulch to the soil around your soil regularly to keep your hydrangea well-hydrated!

I suggest two mulch applications in the spring and summer months. The first one should be done when the soil is beginning to warm up in spring (usually in March or April) and the second application is towards close of July, during the summer’s hottest temperatures.

Mulch is a great option for hydrageas who suffer from heat stress because it cools the roots and reduce the evaporation of water from the soil to maintain a healthy water balance. The roots like to be cool and comfortable, so the mulch layer can stop the sun from directly crashing down on the soil.

If the sun’s at its strongest and pounding down on the garden area, this could make the garden soil become hard, and may even crack. This causes water to flow off the surface and into cracks, but not always get to the root system. Mulch can help alter the surface texture of the soil and help improve the structure, thereby increasing the rate of infiltration due to rain or watering.

Mulch also stops the wind from wicking water from the soil’s surface in the case of an open-air garden.

5. The Best Mulch for Hydrangeas in Full Sun

The most effective mulch is organic material that holds on to moisture. Garden compost leaf mould, leaf mould, and well composted manure are all excellent alternatives as they will continue to enrich the soil and keep the nice loose, friable texture that the hydrangeas love.

The wood chip (or bark) straw, pine needles should be avoided since they don’t hold water well and take a lot longer to break down into soil, and thus are less effective on improving the soil’s structure.

How to Apply Mulch to Hydrangeas

The mulch you choose is to be spread in a 2-inch layer on the ground around the Hydreagea.

Be sure to leave a gap of 6 inches of untreated ground between the mulch layer and the growth of woody Hydrangeas that are above the ground. The growth that is above ground is not able to withstand exposure to moisture as well, and may cause the development of rot.

Spread the mulch on the entire surface. Do not be enticed to dig it or work it into. Digging only disturbs the soil’s beneficial ecology and possibly damage the roots.

Take the time to save yourself the effort by letting the earthworms and the watering and rain create the mulch in your soil in a natural way.


Hydrangeas of this variety Hydrangea paniculata can thrive in full sunlight. It is crucial that your soil remains dry on hot days and that you apply mulch on the soil at least twice a year to maintain the perfect soil structure and balance.

Hydrangeas in full sunlight must be planted in plenty of organic matter, such as (garden mulch or leaf mold) because this can retain moisture while still ensuring adequate drainage.

The task of watering your hydrangeas is a regular chore as the sun beats down and drying out the soil. It is recommended to buy an irrigation system that soaks to to meet the growing demand for water.



Went from a bad gardener to a half-decent one over 10+ years. Super happy to share my tips and tricks with you :)