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Sunday, April 18, 2021

The Guide to Thriving Hydrangeas

With of their bigger flower heads, hydrangeas have an old-fashioned feel to them that is difficult to resist. These beautiful plants are easy to cultivate, grow in almost any soil and produce lots of blooms in attractive colours of clear blue, vibrant pink, frosty white, lavender and rose blossoms which sometimes bloom on the same plant!

It requires following a few simple growing tips to produce healthy hydrangeas. You should be able to enjoy colourful and healthy blooms for many years to come by following these simple tips.


You should be planting your hydrangeas in early spring for best results, but if you are planting in the summer months, make sure that you generously water them. Remember that it is important to protect the stems and the blooms from the hot afternoon sun and strong winds. It would be best to give your plants full morning sun and afternoon shade, however many will flourish in partial shade. Most hydrangeas grow well in rich and moist soils, compost can be added to enrich poor soil. You can also add a slow-release fertiliser and organic matter to the soil. This will start your hydrangeas off on a good note. They bloom from early spring to late autumn.

When planting, dig a hole that’s as deep as the root ball and twice as wide. Put the plant in the hole and half fill it with soil and water. Fill the rest of the hole with soil after the all the water has drained and make sure to water thoroughly afterwards. Space them 1-3 metres apart if you are planning on planting multiple hydrangeas.

Basic care

Make sure to water your hydrangeas regularly for the first few years after planting and during dry spells or the leaves will start to wilt.

Pests and ailments

Hydrangeas are impervious to most when it comes to pests and diseases but not all of them. It’s most common for these diseases and pests to attack in the summer months. The most common diseases that hydrangeas suffer from include; powdery mildew, aphids, spider mites, yellow leaves and leaf spots. All of these are easy to spot and treat if you catch the disease or pest early.

Too much sunlight

Giving your hydrangeas too much sunlight will also affect their health. You can tell that your plants are getting too much sunlight if you notice that blooms are fading fast. Try not to place garden and cut flowers in locations that are directly in the hot, afternoon sun.


These plants can live for a long time with little maintenance and some hydrangea species never have to be pruned, but it’s advised to trim falling flowers and stems back if your plants are looking a bit unruly. Doing this will encourage new growth and more blooms for the next year. The best time to prune any hydrangea is mid-late winter. Some people even wait a bit longer in case of any late frosts, so the ideal time to prune is early spring. Late frosts damage new buds that grow after pruning. Pruning to early can promote new growth so, it’s best to wait.

Quercifolia, Oakleaf varieties:

These varieties of hydrangea requires little maintenance or pruning. Remove dead blooms immediately after flowering. This usually occurs around midsummer.

Bigleaf, Mophead or Lacecap Hydrangeas:

These varieties start flowering from early to midsummer with blooms that often outlast the summer months. This means that buds will most likely appear in late summer or early autumn. Cut back the shoots with flowers, trim the branches and remove any dying flowers for best results whilst being mindful of new buds.

Read more on how to prune hydrangeas here

How to adjust hydrangea colour

These plants are able to produce a range of amazing, different coloured blooms, which range from pink and blue, to lavender but not instantly. Changing the colour of the blooms can take weeks or even months. It is advised to wait at least, until the plant is two years old, to give it time to recover from the original planting shock. Not all hydrangeas’ change colour.  Based on the soil PH, the colour of some Bigleaf hydrangeas-especially Mophead and Lacecap types can change.

The variation in colour depends on where they have been planted and what plant food they have been given. The PH affects the uptake of aluminum and the content of aluminum in turn controls the plants colour. Therefore if you plant hydrangeas in Alkaline soils, with a pH of 6.0 or more, they are more likely to create pink flowers, while the more acidic soils, with a pH 4.5 to 5.5, tend to produce blue blooms. Pink hydrangeas can however be turned blue, when aluminum sulphate is added to the soil, as this lowers the PH level.

In a similar manner blue hydrangeas turn pink when adding lime to the soil which will heighten the PH levels. It’s always important to add these minerals sparingly and dilute them well when attempting to alter the colour of your flowers as too much of one chemical can scorch your plants. If you’re unable to alter the PH of your soil, you may wish to grow your hydrangeas in raised beds or containers to achieve the required hue. White hydrangeas are the only hydrangeas that aren’t affected by PH balances in the soil. Please be aware that it’s easier to change blue flowers to pink than pink to blue.


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