Most folks treat Mimosas (Sensitive Plants) as annual houseplants because they’re notoriously tricky to keep alive through the winter. But don’t worry! You can keep the magic going year after year by starting new plants from seed in the spring. Here’s the lowdown on how to get those seeds growing.
Getting Your Hands on Seeds
You’ve got two main options for sourcing seeds:
- Pick up a packet at your local garden center or online.
- Harvest them yourself from a pollinated plant.
If you want to collect your own, your Mimosa needs to have spent some time outdoors. While it’s a great houseplant, it usually needs a little help from backyard insects to get pollinated. If it was outside during the summer, you’ll see small seeds forming after the blooming period. Wait until the seeds are completely dry and brown, then simply pluck the withered flowers along with the seeds.
Timing is Everything
The best time to start your seeds is in early spring. This gives the young plants plenty of time to establish a strong root system and show off their flowers. While you *could* plant them later in the year, it usually results in a much shorter lifespan for a plant that’s already pretty short-lived.
The Secret Step: Pre-Soaking
To give your seeds the best chance at life, you absolutely have to pre-soak them. Drop them into a bowl of lukewarm water for a few hours. This softens the tough outer shell, which “wakes up” the seed and triggers germination.
Use Sterile Soil
I highly recommend using a sterile seed-starting mix to prevent any nasty mold or fungus from ruining your hard work. You can grab a bag at the store, or make your own by “baking” regular potting soil in the oven at 175°F (80°C) for about 30 minutes.
If you want to skip the soil altogether for the germination phase, coconut coir (Kokohum) is another fantastic, clean option for starting Mimosa seeds.
Planting Your Seeds
Once your seeds are soaked and your soil is ready, it’s time to plant:
1. Fill your pots or trays with the sterile mix.
2. Space the seeds out (don’t crowd them!) and cover them with just a very thin layer of soil.
3. Place the pots in a warm, bright spot and keep the soil consistently moist but not soggy.
Pro Tip: To create a mini-greenhouse effect, slip a clear plastic bag over the pots. This keeps the humidity high, which Mimosas love. Just make sure to pop the bag off for a few minutes every day to let in some fresh air and prevent mold.
