Hydrangea macrophylla

How To Grow Hydrangea macrophylla

Planting Hydrangea macrophylla involves identifying the right soil type, choosing the most ideal planting position, selecting the best variety, and ensuring the plants have the essentials to thrive. The Plant Company has the right advice to ensure success when you are growing Hydrangea macrophylla.

Can You Grow Hydrangea macrophylla In A Pot?

Hydrangea macrophylla grow well in pots and look amazing when managed appropriately. Choose a pot that is no more than twice the size of what the Hydrangea is currently growing in and that has plenty of drainage holes in the bottom. Fill the bottom of the pot to about 1/3 of the way up with potting mix. Do not use soil or compost when growing plants in a container and do not add fertiliser. The Plant Company potting mix has all the nutrients required to sustain the plant for the next 12 months.

Remove the plant from the container it is growing in by either pulling it free or by cutting the bag. The Plant Company recommends cutting the bag, especially for larger grade plants, to minimise any chance of damaging the roots. Place the plant in the hole without removing any of the growing media or cutting the roots. Even if the plant is rootbound, do not cut the roots as this will set the plant back. Refer to our article, Managing Rootbound Plants, for why we don’t cut them. Add more potting mix and firm this around the plant using gentle pressure, then water well. They should be watered twice a week during hot weather and weekly or fortnightly during cooler periods.

The key to having an amazing Bigleaf Hydrangea in a pot is to both keep it fed correctly and not to over-water it. Over-watering is the most common reason Hydrangeas fail.

Is Hydrangea macrophylla Easy To Grow?

Big Leaf Hydrangeas are very easy to grow, but you need to have the basics right. Choose a sunny spot with good drainage. The soil should be well prepared with organic matter added from either compost or sheep pellets mixed in. Feeding your plants in spring with shrub fertiliser or fertiliser for acid loving plants will replenish nutrients and keep them fed for 12 months. Prune your Hydrangea in winter each year to control their growth and encourage fresh growth in spring. They should also be watered regularly during dry periods to keep them flourishing.

Planting Hydrangea macrophylla

Choose a full sun position with good drainage and moderate shelter for your Hydrangea plant. The hole should be dug to at least 50-75% deeper and wider than the container the plant is currently growing in. A planting spade makes the hole digging a lot easier. The Plant Company recommends incorporating compost or sheep pellets into the soil to provide additional organic material, but this is not essential. Do not put fertiliser in the bottom of the hole, rather spread that on the soil surface after planting, and preferably do this when the plant is actively growing in spring.

Remove the plant from the container it is growing in by either pulling it free or by cutting the bag. The Plant Company recommends cutting the bag or container to minimise any chance of damaging the roots. If the roots have been growing in a circle or are all bound up you can tease them apart if you want but this is not essential. The Plant Company does not recommend cutting the roots, even if the plant is root-bound as we have proven this offers no benefit to the plant or its establishment as explained in our article, Managing Rootbound Plants.

Now place the plant in the hole and make sure it is level with the soil surface before filling in around it. Once the plant is set level with the soil surface, add more soil gradually and firm it around the plant using gentle pressure as you go. Scatter shrub fertiliser across the soil surface after planting and the give the plant a good watering.

What Soil Should I Use For Hydrangea macrophylla In A Pot?

Only potting mix should be used when plants are grown in a container. This because the media is pre-loaded with the correct amounts of fertiliser and micro-nutrients to keep the plant sustained with nutrition and actively growing for the next 12-months. Moreover, it holds the correct amount of air and water so the plants can grow as they should.

Often people will try and cut corners and use soil or mixes that contain both soil and potting mix with poor results. The same applies to when plants are potted up with compost as it holds too much moisture. Soil also contains weeds and tends to become compacted in a container, hence why it is not used in this manner. The Plant Company strongly urges you to not cheat or skimp on this vital aspect of growing Hydrangea macrophylla plants well and use potting media!

Where Does Hydrangea macrophylla Grow Best?

Hydrangea macrophylla grows best in a full sun or partial shade position with good drainage. If the drainage is poor or with over-watering, they tend to become stunted and sickly looking. At the same time, of the shade levels are too high, Hydrangeas tend to become “leggy” and flowering is often reduced. The Plant Company generally recommends a full sun position if there is no risk of the leaves being scorched through light levels being too intense. If that is a concern, opt for partially shaded spot.

Moderate shelter is also important so fresh growth is not damaged by wind and this will help produce a better shaped plant overall. Being deciduous, they are tolerant of frost and cool climates. High humidity can cause disease issues, particularly if there is no airflow, so planting in these environments should be avoided. Wherever they are grown, make sure that they will not dry out during summer, and they have plenty of room to expand.

How To Prune Hydrangea macrophylla

Deciding when to prune Hydrangea macrophylla, how to cut them back and how hard is all covered in this series of articles. We want you to empower you with information so you can prune and manicure your plants with confidence and success.

How To Prune Hydrangea macrophylla

Hydrangea macrophylla varieties are pruned each winter to contain growth and encourage fresh, new growth that will bear flowers. The Plant Company recommends they are pruned back to a low crown which has short stems (about 10 cm long) with at least two buds on each stem remaining using secateurs in late winter. Any dead stems should also be removed at this time, along with stems that are criss-crossing or show disease. Young plants will generally be left with five stems whereas older plants can have up to 20 stems remaining. These can be thinned back to 15 if desired which will help produce bigger flower heads. Longer stems can be left on younger plants while they are establishing. In general, the harder the plant is pruned back, the more contained it will grow the next season. Flowering can be affected with hard pruning but that is more likely to cause delayed flowering only.

A mistake often made is to not prune the plants hard enough. This error results in a woodier plant and a much larger plant that can be difficult to contain. It also means more buds will sprout and compete with each other for light and nutrients. The more buds that sprout, the spindlier the stems will become, and flower size is reduced. Therefore, there is always a trade-off between stronger stems that produce bigger flowers and more, smaller flowers.

When Should Hydrangea macrophylla Be Pruned?

Pruning Hydrangea macrophylla is usually undertaken in late winter or in early spring. Don't be tempted to prune too early (i.e., in autumn) as the pruning will stimulate new growth which could be burnt by frosts. When preparing this article, I was astounded to read advice that said DO NOT prune in winter as this removed the flower buds. While this is partially true, you will quickly end up with an out-of-control plant and they are in flower from spring until autumn! It is important to understand that Hydrangeas flower on the ends of new-season growth. The buds remaining after pruning in winter will grow away strongly and produce larger and more stable flower heads than if the plant has 20x more sites to produce flowers from. This is why unpruned plants often produce weak flowers off spindly stems.

Why Prune Hydrangea macrophylla?

Hydrangea macrophylla varieties grow with a rounded, almost ball-like shape, with all of the new growth generally on the outside of the plant. That ball will keep getting bigger and bigger if it is not pruned back and the plant will quickly become woody at its centre. Pruning is therefore undertaken to contain and encourage fresh foliage. This will ultimately result in a more aesthetic plant that produces bigger flowers when done correctly.

Hydrangea macrophylla Care

Caring for Hydrangea macrophylla is about making sure the plants are thriving. Our plant care articles provide the necessary details to give you the greatest chance of success and to grow amazing plants.

How To Care For Hydrangea macrophylla

Hydrangea macrophylla care starts with the planting and we have a whole section that discusses that. So, let’s assume your plant is growing well and you want to keep it that way!

Winter is the perfect time for mulching and pruning your plants. Organic matter such as compost or sheep pellets should be spread liberally around the plants and then overlaid with a mulch. The Plant Company has two very good options for mulch. The first is coco fibre matting which is made from the husks of coconuts. It breaks down to become part of the soil within two years. The second is the black plastic matting which will last 20 years or more. In both instances we recommend stones, bark chip, or other similar products be spread over top of the mulch for aesthetic purposes. We do not recommend adding fertiliser during winter as this is better applied in spring so less is wasted. However, adding organic matter is quite okay.

Pruning can be aggressive or subtle as you like. Typically, plants are pruned to contain growth and encourage fresh, new foliage. Please refer to the section on pruning to ensure you do this correctly. Be sure to take away any pruned material as they can be a source of disease as they begin to rot.

Spring is the perfect time for fertilising the plants as they start to bounce into life. The Plant Company has fertilisers which have been specially blended for different plants and in this instance, our fertiliser for acid loving plants or shrub fertiliser will give them the correct boost and keep them fed for 12-months. A suitable alternative is our organic fertiliser which will also keep them well fed but they will require a secondary application in autumn.

Summer is when the plants need regular watering and this should be undertaken daily on the hottest days. Plants that are establishing need particular attention as their root system will not have penetrated deep enough to secure consistent moisture yet. Summer is also the season when spent flowers should be removed to encourage new flowers to grow.

Autumn is about keeping the plants healthy and continuing to remove spent flowers. Foliar feeding using a liquid fertiliser can be undertaken during spring, summer, and autumn if you have time but this is not essential if solid fertiliser and/or good amounts of organic matter have already been applied. If you think the plants need an extra boost or have some yellowing, however, a liquid fertiliser won’t hurt. The Plant Company recommends some nutrition is applied to the plant in early Autumn as this is when the plants are producing the buds that will grow away in spring. Therefore, making sure these buds are as strong as possible helps put the plant in good stead when it emerges from dormancy.

Check plants for any pest or disease issues during spring, summer, and autumn. If anything is looking a little bit unusual at any time of year, search articles on Hydangea problems to find a solution.

Hydrangea macrophylla Information

This series of articles provides information and answers to questions about Hydrangea macrophylla that have been asked over the years.

Black Leaved Hydrangea

The most prominent black-leaved Hydrangea is Hydrangea 'Tuxedo Red'. The leaves are dark-purple with a dark-green undertone which gives a near black colouring. The flowers on this variety are an elegant red and it typically grows to 1 m tall and the same wide.

Can Hydrangeas Be Transplanted?

Hydrangeas are easily transplanted during winter, and the smaller the plant, the easier and more successful this process is. The Plant Company recommends that the plants are first cut back about 40 cm above ground level. We do this because the transplanting process will remove some of the plants roots, and if we leave all of the foliage and stems, that will put a great amount of pressure on the root system to supply water which they may not be able to keep up with.

Dig out the plant and aim to keep as much soil around the roots as possible. Once the plant is transferred to its new home, be sure to water it well. The two mistakes that gardeners make that often causes the transplanting process to fail are:

1. Watering was not ongoing after transplanting which results in the plant drying out. Watering needs to continue until the plant begins to grow away strongly.

2. Fertiliser was put in the hole at planting. This is a big no-no as it causes root burn and draws moisture away from the roots. Rather, scatter shrub fertiliser onto the soil surface after planting and water the plant well.

Overall, the transplanting process is usually without issue if care is taken during the process.

Hydrangea macrophylla Growth Rate

Hydrangea macrophylla is considered to have a moderate to fast growth rate. It will establish itself and reach a decent size relatively quickly. The actual growth rate can vary as some varieties are naturally more vigorous than others. Ideal conditions like a well-drained soil, a full-sun position, regular watering, and fertiliser will all promote faster growth. Similarly, warmer climates will generally result in faster growth compared to cooler regions. All that said, the typical growth rate is 30 to 60 cm per year with normal growing conditions. It will likely take 3-5 years for it to reach its mature size of 1-2 m tall and wide.

Hydrangea macrophylla Leaves

Hydrangea macrophylla, also known as the Bigleaf Hydrangea, is known for its beautiful and distinctive leaves:

• The leaves are broadly ovate (egg-shaped) and are widest near the base.
• They are relatively large, typically ranging from 10 to 20 cm in length and the same wide.
• The leaves are usually smooth and have a slightly glossy appearance.
• The edges of the leaves are serrated.
• They are typically a deep, rich green colour, providing a beautiful backdrop for the vibrant flowers. Some varieties have leaves with dominant purple overtones. The leaves often turn shades of red or orange in autumn before falling.

Hydrangea macrophylla Size

The size of a Hydrangea macrophylla can vary depending on the specific cultivar, growing conditions, and how much the plant is pruned. In general, they typically grow to 1-2 metres tall and the same wide. However, some varieties may grow larger or smaller than this. The Plant Company has size information with each of the Hydrangea varieties available and in the database.

In colder climates, Hydrangeas may not grow as large as they would in warmer regions. Similarly, plants that are well-watered, grown in sheltered spots, and given plenty of fertiliser will grow larger. Finally, the harder plants are pruned back during winter, the smaller the plant become during the growing season.

What Is Another Name For A Macrophylla Hydrangea?

Macrophylla hydrangeas have several other names, depending on the context and specific variety:

• Bigleaf hydrangea (most common)
• French hydrangea
• Mophead hydrangea (for varieties with rounded flower clusters)
• Lacecap hydrangea (for varieties with flat flower clusters with prominent center florets)
• Snowball plant (for varieties with white blooms)

What is Bigleaf Hydrangea macrophylla?

A Bigleaf Hydrangea is another name for Hydrangea macrophylla. Specifically, it is a deciduous shrub and its large and vibrant flower clusters. Bigleaf Hydrangeas are also called "French Hydrangea" or "Mophead Hydrangea".

Hydrangea macrophylla is native to Japan and are very popular garden plants due to their beauty and ease of care. The flowers are the most striking feature which are large and rounded and held as flattened clusters. The flower colour of the pinks and blues will vary depending on the soil's acidity level. With an acidic soil the flowers are blue, and otherwise pink with neutral and alkaline soils. These are produced during summer and autumn.

The foliage comprises leaves that are large and lush. They are typically dark green with serrated edges and develop yellow, orange, or red tones in autumn before falling. It generally grows to 1-2 m tall and wide.

Why is Hydrangea macrophylla called Big-Leaf Hydrangea?

Hydrangea macrophylla is called "Bigleaf Hydrangea" because it has remarkably large leaves compared to many other shrubs. The leaves can easily reach 10 to 20 cm in length. for a shrub.