How To Grow Hydrangeas From Seed

There are many ways to add height and color to your garden, but one of the most surefire ways to cultivate a dramatic display that doesn’t need a lot of attention is using hydrangeas.

It also helps that there are many different types to choose from, including lace cap hydrangeas, mophead hydrangeas, mountain hydrangeas, and panicle hydrangeas. 

Some are more suited to different growing conditions, but they are easy to care for and will treat you to seas of color all summer and into fall, no matter what type you choose.

Let’s take a look at how to grow hydrangeas, and if it’s possible to grow them from seed.

What Are The Best Ways To Grow Hydrangeas?

The easiest way to grow a hydrangea is to start with one that’s already established. Garden centers regularly sell hydrangeas in pots, and it won’t be long before it grows to a bigger height when you get it settled in your garden.

There are some advantages to this. Firstly, the only thing you need to do is to plant the hydrangea and get it used to its new home, which is much easier than raising hydrangeas from seed or cuttings.

All the hard work is done for you. It also means that because this plant is bigger, it’s less likely to suffer in a brand-new position, and will also weather some pests while you treat the plant.

But this can be costly, especially if you go for several mature hydrangeas. 

This is why many gardeners propagate their plants by swapping cuttings with each other, taking a cutting from an existing plant (NOT from a plant in a nursery, this is stealing), or raising plants from seed.

The easiest way to propagate hydrangea is to take softwood cuttings from an existing hydrangea plant. 

This is so much quicker and easier than attempting to grow them from seed – as some plants are quite difficult to germinate, and it is the widespread method for this particular type of plant.

But, if you fancy a challenge, you can try growing them from seed, but be warned – this process will take longer. There is a reason why hydrangea seeds are not sold commercially very often.

It’s also worth noting that the money you spend on compost and the time you spend raising them is arguably more expensive than buying an existing plant or raising a hydrangea from cuttings.

Having said that, let’s get to it!

How To Grow A Hydrangea Plant From Seed

Collect The Seeds From The Parent Plant

The first thing you need to do is to collect some seeds, of course. The seeds won’t be ready until fall when the flowers have finished, and the seed pods are crinkly to the touch.

Once the seed pods have dried out, and are just starting to open, put a paper bag over the top. Cut the dried head off the plant, and shake it in the bag to release the seeds. 

Store The Seeds For Spring

When you collect seeds from any plant, most need to be stored for the following spring, so there is an exercise in patience!

The best way to store seeds until then is within a labeled paper bag, stored safely in a metal tin away from heat sources. 

You may be tempted to skip labeling the bag, but this would be a mistake. By spring, it’s unlikely that you’ll remember what is what, especially if you have collected other seeds at the same time. 

Sow The Seeds

Two months before the last frost, start sowing your hydrangea seeds. Sow them lightly onto the top of damp and rich seed compost. 

Press them onto the surface so they are in contact with the soil, but do not cover them with soil. Place the seed tray on a warm windowsill with plenty of light, but no direct sunlight.

Keep Misting The Soil

You will want to keep the soil damp while the seeds germinate, which can take up to a month. 

Transplant The Young Hydrangeas

When you see your new hydrangeas have two sets of true leaves (these are leaves that look the same as a mature hydrangea, rather than those of a seedling) then they are ready to live outside.

The best time to transplant them outside is in spring and fall, but you will need to do this gradually. 

Start with bringing them outside for a couple of hours in the day in their pots, and taking them in at night. 

Gradually increase the time until they are outside all the time, at which point they are ready to be planted in the ground.

Dig a hole that is roughly twice the size and width of the roots, somewhere suitable for the hydrangea species you are planting. Preferably near a wall or fence to give them a bit of protection.

Fill in the soil, and mulch around the surface to help suppress any weeds. Give the roots a good soaking, and you’ll want to soak them at least once a week (weather permitting) to allow the roots to establish.

How Long Does A Hydrangea Take To Mature?

It depends on the variety. Some hydrangeas will take only a few years to mature (depending on when you prune it, too), while others will take a little longer. 

If you can give your hydrangeas the ideal conditions they need, this will speed up the process a little, as well as result in better blooms.

Leave a Comment