There is something quite magical about hydrangeas in full bloom. Bursting with dramatic colorful flowers and bold green foliage, it’s no wonder they are commonly seen planted in yards and gardens.
While most home gardeners purchase a shrub from a plant nursery, or take cuttings from existing plants for propagation, you can also choose to grow them from seed.
Starting hydrangeas from seed may take a bit of time and forethought, but if you are up for the challenge, it can be a rewarding project.
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Hey there, fellow garden enthusiasts! I’ve been growing hydrangeas for years, and lemme tell you – collecting seeds from these beautiful shrubs isn’t as complicated as some folks make it sound. Today, I’m gonna share my tried-and-tested method for harvesting hydrangea seeds that’ll help you expand your garden without spending a dime!
When’s the Perfect Time to Collect Hydrangea Seeds?
The timing is super important here! You wanna wait until
- Late summer or early fall
- Flowers have faded and turned brown
- Blooms look papery and dried out
- Seed pods are slightly open but haven’t dispersed yet
What You’ll Need
Before we start, grab these supplies:
- Paper bags (lunch bags work great!)
- Clean pruning shears or scissors
- White paper or plate (helps you see those tiny seeds better)
- Air-tight container or envelope for storage
- Labels and marker
Step-by-Step Guide to Collecting Hydrangea Seeds
1. Prep Those Flower Heads
First things first – we gotta catch those seeds before they fly away! Here’s what I do:
- Find browning flower heads that are starting to dry
- Carefully slip a paper bag over each flower head
- Secure the bag around the stem (I use twine or rubber bands)
2. Snip and Dry
Now comes the fun part:
- Cut the stem just below the bagged flower head
- Keep the bag on – trust me, you don’t wanna lose those precious seeds!
- Find a dry spot away from direct sunlight
- Let ’em dry for another 1-2 weeks
3. Collect Those Seeds
After drying:
- Give the bag a gentle shake over a white surface
- Look for small, round seeds (they’re usually tan to black)
- Separate seeds from flower debris
- Store clean seeds in labeled containers
Pro Tips from My Experience
Listen up! Here’s what I’ve learned from my successes (and mistakes!):
- Choose the Right Plants: Pick seeds from healthy, disease-free hydrangeas
- Don’t Rush: Green flower heads won’t give you mature seeds
- Be Thorough: Collect from multiple flower heads to increase your yield
- Stay Organized: Label everything! Trust me, you’ll thank yourself later
- Check for Quality: Toss any moldy or damaged seeds
Growing Your Hydrangea Seeds
Wanna know the cool part? Each seed carries unique genetic material. so you might end up with something totally different from the parent plant! Here’s how to grow ’em
Starting Seeds
- Plant indoors about 2 months before last frost
- Use sterile seed starting mix
- Keep soil temp around 70°F
- Don’t bury seeds too deep – they need light!
Transplanting
- Move seedlings outside after frost danger passes
- Choose spots with morning sun and afternoon shade
- Add plenty of compost to the soil
- Water regularly while establishing
Common Questions I Get Asked
Q How long will my seeds stay good?A About a year when stored properly in a cool, dry place.
Q: Will my seeds produce exact copies of my hydrangea?
A: Probably not! That’s part of the fun – you might get some unique variations.
Q: How long till I see flowers?
A: Be patient! Usually takes 3-4 years for seed-grown plants to bloom.
Final Thoughts
Collecting hydrangea seeds is such a rewarding process! Sure, it takes some patience, but there’s nothing quite like growing new plants from seeds you’ve collected yourself. Plus, it’s basically free gardening – who doesn’t love that?
Remember, every gardener’s experience is different, and that’s okay! Don’t get discouraged if things don’t work out perfectly the first time. Keep trying, and before you know it, you’ll have a gorgeous collection of unique hydrangeas that you grew from seed.
Gather the Flower Heads
The first step is to acquire seeds. You can do this by collecting flower heads a few weeks after the colorful blooms have begun to fade and turn brown.
The exact timing of this depends on your climate and the variety you are growing, but typically this will be sometime in the fall. You want the flower heads to be completely dry before you collect them.
Cut several of the flower heads off of the plant and place each inside its own brown paper bag. Hang the bags in a cool dry place for about a week to finish drying.
Once they have completely dried out, shake the bag to help detach the seeds from the flowers.
While the blooms may be large, the seeds themselves are very small. You may wish to empty the contents of the bags onto a white paper plate or piece of paper to help you identify the seeds and separate them from the debris.
Seeds may be sown immediately, otherwise you should place them in labeled paper envelopes and store them in a cool, dry location. If they are viable, they should keep up for up to a year.
Sow in flats or individual nursery pots filled with a well-draining potting mix. Gently press three to five seeds onto the surface of the soil in each cell or pot, taking care not to bury them, as light is necessary for germination.
Set the tray near a sunny window or under grow lights, and keep the soil evenly moist, but not waterlogged, until germination, which should take about two weeks.
When seedlings emerge, thin them so that there is one plant in each starter cell or pot.
Once they have two to three sets of true leaves you can carefully transplant them to one-gallon pots filled with potting mix. Ensure that the containers you choose have one or more drainage holes in the bottom.
Keep containers in a location that receives ample sunlight, such as a south facing window, and continue to care for them for a few months until the roots are well established and growth is apparent.
How to Propagate Hydrangeas from Seed
Before you get started, it’s important to understand that unless you are collecting seed from a species plant, most will not grow true to the parent.
Over the years, plant breeders have created a large number of cultivars and hybrids, and these may not produce viable seed, and if even they do, the resulting plant may differ considerably from the parent.
Hydrangeas do not produce single blooms, but large inflorescences consisting of tiny, inconspicuous fertile flowers, and large, decorative infertile sepals. In the case of the large mophead cultivars, their flouncy round blooms may contain few, if any, fertile flowers.
Lacecap hydrangeas, with their visible fertile flowers surrounded by colorful sepals are typically a better option for collecting viable seed than mophead varieties, as are oakleaf or smooth types.
By contrast, rooting cuttings will produce clones of the original plant. If you prefer to propagate your hydrangea from cuttings, check out our guide to learn more.
But if you’re up for a little experimentation, collecting and starting seeds from your own plants may produce new, unique varieties!
Here’s how to do it: