Hibiscus
is a gorgeous tropical shrub that thrives in the warmer environments of the
southern United States. Although most gardeners like to purchase young hibiscus
plants from garden centers or nurseries, you may want to try your hand at
sowing hibiscus seeds.
While it does take longer to grow hibiscus from seed, it can
be a rewarding, productive activity, and an inexpensive way to fill your garden
with these amazing plants. Let’s learn how to plant hibiscus seeds, step by
step.
Hibiscus Seed Propagation
You can plant freshly harvested hibiscus seeds directly in
the garden in autumn if you live in a very warm, frost-free climate. However,
most gardeners prefer to start seeds indoors. Here’s how to go about it:
Nick the seeds with fine grade sandpaper or the tip of a knife to allow moisture to enter the seed. This step isn’t absolutely required, but it provides a jump start on hibiscus seed germination. Nicked seeds usually germinate in a month or less, otherwise, hibiscus seed germination may not occur for several months.
After nicking the seeds, soak them in warm water for at least an hour, or overnight.
Fill a container with good quality seed starting mix. (Avoid
mixes with fertilizer pre-added). Any container with a drainage hole will work,
but if you’re planting several seeds, celled seed trays are convenient.
Water the seed starting mix until it’s evenly moist but not dripping wet or soggy. Hibiscus seeds will rot in too much moisture. Plant hibiscus seeds to a depth of about one-quarter inch to one-half inch (.5-1 cm.).
Hibiscus seed germination requires heat, so a location where temps are maintained between 80 and 85 degrees F. (25-29 C.) is ideal. You may need to set the tray on a heat mat to provide adequate warmth. Cover the tray with clear plastic or slide it into a white plastic garbage bag.
Check the tray daily. The plastic will keep the environment
moist, but it’s critical to water lightly if the seed starting mix feels dry.
Remove the plastic and put the trays under fluorescent bulbs or grow lights as
soon as the seeds germinate. The lights should be on sixteen hours per day.
Move the seedlings to individual, 4 inch (10 cm.) pots when the stems begin to get woody and have several sets of leaves. Handle the seedlings carefully as the stems are easily broken. At this point, begin feeding the seedlings an all-purpose, water-soluble fertilizer diluted to half-strength.
Gradually move the young plants into larger pots as they
grow. Plant the hibiscus plants outdoors when they’re large enough to survive
on their own. Be sure there’s no imminent danger of frost. Otherwise, you may
continue to grow them as houseplants but allow them to enjoy the warmer months
outdoors.