Zinnias come in a wide variety of shapes, sizes, and colors while being easy to grow and care for. These wonderful plants can be grown in the garden or in pots, creating a lot of versatility.
Most people purchase seedlings or packets of zinnia seeds, dividing the plants when they want more of the same specimen. But did you know it’s actually easy to harvest zinnia seeds from flowers?
Here’s what you need to know to ensure a nice supply of these wonderful plants for yourself or as gifts for friends.
Harvesting Zinnia Seeds?
Harvesting zinnia seeds can be fun and easy, but there are still a few rules to be aware of.
Let’s look at some of these important points first so you can plan ahead and avoid any unwanted surprises.
Know Your Zinnia
When you’re growing an actual species of zinnia, seed propagation is a snap. However, some zinnias will give you trouble if you try to grow them from seed.
Cultivars And Hybrids
Cultivars can be problematic because of how they’ve been created.
Much like how the AKC (American Kennel Club) won’t recognize a new dog breed until it’s able to reproduce more of itself, Mother Nature is very reluctant to let cultivars be cultivars.
This means most cultivars will produce seeds that revert to one of their parent plants instead of the cultivar itself.
As a result, your garden will quickly turn into a box of chocolates if you try to use cultivar seeds.
In addition, some cultivars may be sterile, making an effort completely worthless.
Natural hybrids are a bit different. Like cultivars, you can’t be sure what you’ll end up with when growing from seed.
However, hybrids are more like dogs because their seeds can eventually retain the hybrid’s traits, resulting in an official variation or subspecies.
These plants have gained Mother Nature’s support, so it’s safe to grow them from seed once you know the plant is genetically stable.
This is where things get a little complicated, as a small number of cultivars have actually achieved genetic stability and can be reproduced via seeds.
Known as open-pollinated zinnias, there aren’t many of these out there, but here’s a list of the best-known examples:
- ‘Cactus Bright Jewels’
- ‘California Giant’
- ‘Canary Bird’
- ‘Candy Cane’
- ‘Cut ‘n’ Come Again’
- ‘Green Envy’
- ‘Jazzy Mix’
- ‘Red Spider’
- ‘State Fair Mix’
One of the worst surprises when growing from seeds is finding out two of your zinnias were cross-pollinated, resulting in surprise hybrids.
This isn’t a problem if you’re only growing one or two species, but if you have a lot, this could be a problem.
A popular workaround is using clear plastic bags to isolate flower buds.
Begin by selecting which flowers you want to reproduce and which you don’t.
Loosely tie some clear plastic bags over the buds you want to keep pure (or the ones you don’t want to be pollinated), ensuring there’s room for them to bloom.
This will result in pollinators being unable to access the protected flowers, and you can bag pollinated flowers and unbag the unpollinated ones until everything’s been visited.
This method can get a little sloppy, especially if you have a large field, so while this trick works great for some, your mileage may vary.
When To Harvest Zinnia Seeds?
Now that we’ve gone over the complicated stuff, let’s look at the timing and get those seeds ready!
It can be a little frustrating to harvest seeds because they’re a practice in patience.
Soon after pollination, the flower head will begin to wilt and dry out.
You can deadhead some other zinnia flower heads at this time, but the ones you wish to harvest have to remain.
This means you’ll have some pretty ugly spent flowers for a little while, but don’t worry, this is what you actually want.
The seed heads won’t be ready to harvest until they’ve turned dark brown and are dry to the touch.
Check the plants occasionally for pests or diseases while you wait.
This is especially true for powdery mildew, which can infect the seeds and ruin your harvest.
Once you’re down to a pretty bare seed head, it’s finally time to harvest, which you can do by cutting or pinching each head.
Be sure to keep the heads and their seeds separated and clearly labeled at all times from here on out so different species won’t get mixed up.
How To Remove The Seeds
This is the fun part for some, while others find it the most tedious.
Lay a paper towel or plate over your work area and gently hit one of the seed heads to dislodge all of its seeds.
You can also rip the head apart and manually pluck each seed.
Once the seeds are removed, sift through, removing any debris and plucking off any remaining spent petals.
Set the seeds aside on a marked paper towel for a couple of days to help ensure they’re fully dried out.
Finally, it’s time to put your seeds into storage.
You’ll need some small envelopes, paper sandwich bags, and lidded glass jars to protect them further.
Note that you can put more than one bag or envelope in each jar.
Mark the name of the zinnia on your bag or envelope and the date, and place the seeds inside. You may wish to tape or seal the package shut to ensure no seeds escape if disturbed.
Next, seal the packets in your jars, which you might also wish to label with the date and names of the zinnia seeds inside.
You can later give some of these homemade seed packets to friends and family as gifts or use them for your own garden.
So why add the date?
Zinnia seeds have shelf viability of 3 to 5 years. By dating the packet, you can essentially figure out the use-by date, which helps you prioritize older seeds over newer ones.