One of the best parts of summer and fall gardening is the many fresh herbs, spices, and other edibles you can grow in your garden. I’m partial to those you can brew into teas and include in cooking. One of the most generous plants I’ve grown in that regard is roselle (known botanically as Hibiscus sabdariffa).
I enjoyed tons of Jamaica tea in Guatemala during my time there. I noticed roselle – the plant that the tea comes from – is highly important in Mexico and Central and South America. However, it surprised me to find the plant originated in West Africa. The history related to its importance there was interesting as well.
All this led to me finally purchasing a roselle from a local nursery and planting it in a raised bed. This fall has proven to be a goldmine of roselle harvesting and tea-making. I’m excited to share what I learned about this awesome plant and discuss the ins and outs of growing, harvesting, and storing its interesting flowers.
Roselle Overview
| |
Classification
The vibrant roselle belongs to a group that includes globally important crops like okra, cacao, cotton, and durian.
This simply bursting plant is a member of the mallow family, Malvaceae. In this family are many beloved plants of 244 genera and 4225 species. Some of the world’s most important crops are classified here. Okra, cacao, cotton, and durian are all members and are hugely popular worldwide.
As the genus name suggests, roselle is a hibiscus plant. There aren’t many species of Hibiscus that are edible, but sabdariffa and a few others are used in culinary practice. This species made its way worldwide from Africa via various trade routes.
Leaves
The plant features oppositely arranged, palmate leaves with three to five deep lobes.
The leaves of this plant are palmate, with three to five deep lobes. They are arranged oppositely on branching stems that grow up to a few meters in height. Its leaves are rough and range in color from green to reddish.
The plant stems also take on a reddish tint as it matures. Roots can become massive and thick, much like other mallow family plants.
Flowers
The hibiscus flowers, with distinct stamen and large white to pink petals, bloom briefly from late summer through fall.
The flowers have that distinct hibiscus structure, with a pronounced stamen and large petals that seem to be of one formation. They are white to yellow and pink at times. They are slightly smaller than ornamental hibiscus flowers and bloom in late summer through fall.
Each bloom lasts for about a day and closes quickly. At the base of the flower, a pronounced calyx supports a large, plump seed pod. The calyx is a vibrant red color and is used for hibiscus tea.
The flowers are also excellent for attracting pollinators to the garden. In fact, in studies conducted on coffee plants, hibiscus proved most effective in boosting pollination compared to others. You can also expect visits from bees, butterflies, hummingbirds, and hoverflies!
Propagation
Mature roselle seed pods can be opened to extract seeds for planting or propagate new plants through stem cuttings.
As the seed pod matures and dries on the plant, the seeds within can grow new roselle plants. You can open the pods and extract the seeds to plant elsewhere. Another option is propagation by stem cutting.
Snip a stem below a leaf node at a length of about five to six inches. Remove all but two to three sets of leaves. Then, dip the stem in rooting hormone and place it in a fertile growing medium. In a couple of weeks, if you keep the soil moist and the temperature mild (65-85°F/18-29°C), your new plant will take root.
Roselle is hardy in zones 9 and 10 and can survive areas with mild winters, especially with protection in places where it’s not usually hardy. Therefore, in temperate areas, this plant can be perennial. That means no propagation is necessary in these areas unless you want to expand your roselle plant garden.
Planting
Sow mature roselle seeds in spring for optimal germination between 75°F and 85°F.
You can directly sow mature roselle seeds as soon as the soil can be worked in spring. Seeds germinate best in moderate weather, at soil temperatures between 75° and 85°F (24° to 29°C). Plant two to three seeds at a time in holes that are ⅔ of an inch deep. Keep your plants at least 3 feet apart. They will spread!
You can transplant young plants in spring when temperatures are at least in the 60s (roughly 15°F). Depending on where you live, this occurs from March to May. You want to plant before it gets too hot for adequate root development and after the cool weather of winter has passed.
Those living in areas with mild fall seasons can plant as soon as temperatures cool in early fall.
How to Grow Roselle
Once you’ve planted your seeds or young plants, it’s time to get ready to maintain this baby. One thing is for sure: you will be harvesting a ton of buds or even simply enjoying the beauty of a massive roselle bush.
Containers
Roselle thrives in spacious containers with proper drainage, accommodating various materials.
Roselle can manage to grow well in any container that is large enough and has good drainage. Remember, these plants take up lots of space when they’re mature, growing taller than most people and a few feet wide. All materials work here, including plastic, terra cotta, and wooden planters.
When selecting a container, look for one at least 15 gallons in size for best results. Some guides suggest at least 5 gallons, but your plant’s roots won’t have as much room to grow, and you won’t have as many blooms using a container of that size.
Light
Roselle plants thrive in full sun, but afternoon shade or dappled sunlight is recommended in high-heat locations.
Full sun is perfect for roselle plants. If you live in a place with high heat during the summer months, afternoon shade or dappled sun is better. In hot summers when shade is not readily available via trees and taller plants, shade cloth is useful.
Day length is an important factor in the production of seed pods. As the days shorten over the fall, the plants settle into a production cycle. You’ll notice tons of flowers as fall sets in and the same number of calyces ready to harvest in the mid-season.
Soil
Roselle requires fertile, well-drained soil, and using hugelkultur in a raised bed creates nutrient-rich, moisture-retentive soil.
Fertile, well-drained soil is a must for roselle. Mine is planted in a raised bed that contains a hugelkultur. Hugelkultur is a method of building soil by layering wood logs, branches, twigs, leaves, and compost. The result is a rich, moisture-retentive soil that is full of micronutrients.
Outside of building soil this way, good-quality potting soil is great for containers. Raised beds with high-quality, fertile soil that drains well are perfect, too.
Water
Keeping the soil consistently moist, especially in the top inches, is essential for roselle growth.
In hot areas, daily watering is best. Use a drip line, ollas, or soaker hoses for best results. Hand watering works, too, if you water early before the sun can rise and evaporate your efforts.
But the former three watering methods give you the best results and deter any splashback that can happen in a hand watering situation. Keeping the soil moist down to a couple of inches is also a good practice for growing roselle. Use a finger to test and see if this is the case before you water again.
In a hugel bed, I don’t have to water as much because the decomposing material in the bed holds moisture quite well. I’m writing this in the middle of an intense drought, too. So once established, roselle can be a water-wise plant.
Climate and Temperature
Roselle thrives as a woody perennial in temperatures of 65° to 95°F with humidity around 70%.
The native climate of this plant of Central and West Africa has median temperatures between 65° and 95°F (18 and 35°C). In regions like these, the plant is grown as a woody perennial in between other crops.
While high humidity isn’t a must, the indigenous climate roselle grows in generally has an average humidity percentage in the 70s. Keeping the soil around the plant moist in drier areas will maintain higher humidity.
You’ll need to get into the idea of planting roselle seeds annually if you live outside zones 9 and 10. In zones nearby, you can try to protect your plant by cutting it back slightly and layering a few inches of mulch around the base to protect it in the cold. In this way, it can be a tender perennial close to its hardiness range.
Fertilizer
Fertile soil with periodic well-rotted compost is sufficient for roselle.
While fertile soil that receives one or two applications of well-rotted compost throughout the season is enough, you can apply a higher potassium fertilizer during its active growth stages. Therefore, in spring and summer, sprinkle a little bit of 3-4-4 organic fertilizer around the base of the plant every other week.
Maintenance and Care
Giving your roselle bush a spring trim helps maintain its shape and overall health.
Pruning your roselle bush isn’t necessary, but perennial bushes benefit from a few snips in spring. In this case, take all of a branch but the part that holds the first two buds. Remove any dead, discolored, or diseased leaves that may arise in the growing season.
You may notice your plant leaning over or branching out. This is normal, and any pruning you do to maintain its shape should follow the same guidelines above.
Enjoying Roselle in the Kitchen
While this hibiscus is stunning in an ornamental garden, you’re probably interested in growing it for making teas, jams, and jellies. Let’s discuss how to harvest at the right time, in the right way, and how to store the fruits of your labor.
Harvesting
Harvest the plump, red calyces with clean scissors, selecting the best for kitchen use and saving some for seed extraction.
As mentioned in the section about H. sabdariffa’s flowers, when they bloom, they last only one day. After about seven to ten days, the flowers have faded and most likely fallen off the plant. What remains is a plump, bright red calyx that holds a seed pod.
At this time, take a pair of clean scissors or harvesting snips and remove the calyces. Take only the most plump ones for your kitchen. You can save some to extract seeds and plant them later. The rest can be processed.
To remove the calyx for use in the kitchen, simply cut it from around the seed pod, remove the pod, and you have the material needed for any tea, jelly, or syrup you like!
Storing
For longer storage, dehydrate the calyces in a dehydrator for four to five hours or with a fan for two to three days.
Once you’ve removed them, you can process the calyces further for longer storage or use them within one to seven days. If you go with the latter of these, keep your harvest in an airtight container in the refrigerator.
Dehydrate the calyces, which will last for one year, in an airtight container stored in a cool, dry place at room temperature. Just dehydrate them in a dehydrator for four to five hours at 135°F (57°C). Depending on the conditions present, you can dry them with a fan, which takes roughly two to three days.
Pests and Diseases
For scale, aphids, and mealybugs, remove them manually or use neem oil or insecticidal soap.
Scale, aphids, root rot, and powdery mildew are all potential concerns when growing roselle.
For scale and aphids, begin treatment with simple removal of the insects. Aphids and soft-shelled scale insects (like mealybugs) are easy to remove by wiping with a damp cloth that has a tiny bit of rubbing alcohol applied to it.
Hard-shelled scale can be popped off the plant with an alcohol-soaked Q-tip. If hand removal doesn’t do the trick, neem oil or insecticidal soap will. Spray these before sunrise, and avoid using them around peak pollinator hours. They can cause damage to beneficial insects as well as pests.
Root rot will arise when the plant’s roots are stressed via standing water, improper planting, or compacted soils. This condition is actually a fungal disease that strikes at the root level. If you notice a soft crown or see blackened roots, you may be dealing with root rot.
There is no cure for root rot, and prevention through proper planting and care is best. Potted roselles suffering from root rot can be transferred into a new pot with new soil, though.
Powdery mildew is another difficult problem to deal with. If you see powdery masses on upper leaf surfaces, you may have some mildew. Start by removing leaves that are infected. If the masses spread, you may need to remove the entire plant.
Most of the time, however, plants can handle a slight powdery mildew infection and still pull through. Use sprays as a last resort, and keep your plant healthy to prevent pests and diseases from taking over. Rotate your crops to ensure existing infections don’t spread to other plants.
Final Thoughts
Roselle is one of the easiest plants to grow during warmer seasons. It’s a beautiful and interesting plant that will bring a lot of pleasing views in the garden and some tart flavor to your kitchen.
Especially if you’re in zones 9 or 10, adding a roselle bush to your landscape is worth it! Don’t sleep on this awesome plant.
