How to Grow Stevia Rebaudiana from Seed
Stevia Rebaudiana is the plant whose sweet leaves are far stronger than sugar, but without the calories.
A tender perennial, Stevia can be grown at home for your own use fairly easily, and today we are going to look at exactly how to grow Stevia from seed.
Once you have your seed, you could have a never-ending supply of Stevia Rebaudiana plants, as each plant produces flowers and seed at the end of the growing season in the autumn.
If you live in USDA zone 9 and above, your plant will survive outside from one year to the next, dying down in winter and regrowing in spring.
Elsewhere, deep frost is likely to kill your plant off unless you take it indoors to overwinter.
If this happens, simply plant more seeds the following spring, and start again.
Stevia Rebaudiana is a healthy alternative to sugar and it is well worth growing this wonderful 'sugar plant' to sweeten your drinks and foods instead of the fattening cane sugar we are used to.
Being a completely natural product, it contains none of the potentially harmful chemicals found in many sugar substitutes, and has been used safely for millennia by many people in Paraguay and Brazil where the plant grows naturally in the wild.
Even if you have no weight problems, and no issues with sugar, Stevia is a fun plant to grow at home, in view of its special properties.
Planting Stevia seeds
I bought some seeds from someone on eBay, and scattered a few of them on the surface of a compost filled pot.
I then added a thin layer of pebbles. Vermiculite would have been better, but I had none in.
The seeds are designed to be airborne, just like the seed on a dandelion.
I would show you them, but I lost the packet. Out of over 3,000 seeds, I only used a few.
I then placed the pot in an unheated greenhouse, and kept it well watered on hot days.
The seedlings took about 2 weeks to come through, and then, out of about 30 planted seeds, only 3 germinated.
I think that was possibly because I gave the pot too much water and some suffered damping off.
Out of the 3 germinated stevia seedlings, one died at the second set of leaves stage.
The biggest one seemed healthy and I moved it to a pot of its own, taking care to handle it only by the leaves, and transplanting its whole root-ball.
It promptly died!
For that reason, I made no attempt to move the final plant, and it is now growing strongly and healthily.
How to Propagate Stevia
Obviously, I would like to have several stevia plants, and so I have taken cuttings.
I chose a side shoot that had new growth coming from the leaf axil at the bottom of the stem, knowing that the plant would benefit from its removal with the growth of new side shoots.
- Cut the stem cleanly just above the lower leaf axil, leaving just 2 sets of leaves on the shoot.
- Remove or cut in half the lower leaf set, and dip the stem in firstly into water, and then into a hormone rooting powder.
- Shake off the excess, and plant into a pot of damp, half compost/half sharp sand mix.
- Plant as deep as the leaf axil from which you chopped the leaves off.
- Place the whole pot inside a sealed plastic bag, and situate in a bright place but out of direct sunlight.
My plants are nestled between the taller leaves of the hippeasturm plants.
When new growth can be seen in the cuttings, it is time to remove the bag, and place the rooted stevia cutting in full sunlight.
It is really important to give stevia cuttings 16 - 18 hours of daylight, and so I took my cuttings just a few days before the summer solstice.
In my part of the world, midsummer daylight hours are around 18 - 19 hours.
If you are growing stevia in another part of the world that gets less light - equatorial regions, for example - then you will need to place an artificial light above your stevia cuttings for at least part of the time between dusk and dawn.
There are many grow lights available on the market you can use. Choose a low power consumption LED grow light and place your cuttings underneath.
Stevia needs a heat of 70ο - 75οF both to grow and to germinate, but even in cooler climates, an unheated greenhouse can offer this in summer.
If not, choose a sunny window-ledge inside your house, preferably in the kitchen where you can harvest those sweet leaves whenever you want.
In cooler climates, stevia rebaudiana will need to be moved indoors in the winter, to keep it in a frost-free environment.
Results of my own experiments from taking stevia cuttings
The plant cutting that you can see in the photos above took 6 weeks to root, after which it was removed from its plastic bag and placed on the automatic watering growing shelf I have in my greenhouse, where it is thriving.
Meanwhile, I had taken some more cuttings, given them no hormone treatment whatsoever, and simply potted them in plain potting compost in a pot, which was then watered and placed inside a sealed plastic bag.
Those cuttings took about 3 weeks to root, (over a period in July/August) and they are now healthy looking plants that actually show more growth than the ones dipped in hormone rooting powder.