Rosella makes one of my favourite jams and as it is such an easy plant to grow in the tropics and subtropics I try to grow a crop each year. Over summer and autumn, the plants look stunning in the garden as they come into flower. The brilliant red fruit are eye catching, particularly when backlit by the western sun.
Rosella (Hibiscus sabdariffa), also known as Roselle, Indian Sorrel, Jamaican Sorrel and Florida Cranberry is an iconic plant in Queensland, where it has been a beloved staple for some 150 years. Rosella seemed to lose popularity in the ‘90s and ‘naughties’, and I thought it would disappear from our gardens. I’m pleased to see it is now valued by a new generation of gardeners and perhaps this has been fuelled by the renewed interest in preserving and cooking. Thankfully you can now find it for sale in garden centres each spring.
If you are not familiar with Rosella, it is an annual shrubby hibiscus that produces brilliant crimson ‘fruit’ along its branches. These ‘fruit’ are in fact a fleshy calyx that develops around the seedpod. This calyx consists of 5 partially fused sepals and a collar of bracts, and develops after the red-eyed cream hibiscus flowers fall. The rich acid flesh of the calyx has the consistency of a fruit leather and taste of cranberries.
Rosella was once grown commercially in Queensland, and in the late 19th and early 20th Century two factories exported considerable quantities of jam to Europe.
The plant is grown from seed each year and the trick is to get it in the ground as soon as the warmer weather arrives. The plants are day-length sensitive and they produce quantities of foliage and branch structure as the day length increases, but after the summer solstice as the days start to shorten, the plant is triggered into producing flowers and then ‘fruit’.
I sow seeds directly in the vegetable patch in my subtropical garden when the coconut oil in my kitchen goes from a solid to a liquid – generally around early August (February in the northern hemisphere). In warmer areas sowing would be earlier, while in warm temperate areas sowing would be later, generally around September (March in the northern hemisphere).
Plants grow quickly into bushes some 1 to 1.5 metres across and they benefit from transplanting to 1 to 2 metre intervals once they are some 100 mm (4 inches) tall. They enjoy moist, friable well-worked soil with plenty of composted organic matter, manure and the addition of a balanced ground rock mineral fertiliser. I grow my plants in my vegetable garden and crop fast growing vegetables around them until they get too large and dense. The secret to get a great crop is to keep plants well fed and well watered leading up to the longest day to get the bushes as large as possible.
Rosella is surprisingly pest free. Even the wallabies who frequently browse my vegie garden avoid the plant. I would expect birds to be attracted to the red calyxes but this has not been the case. The only pest I have come across are the black aphis that may appear on the calyx late in the season. If grown on wet, poorly drained, clay soil, plants may suffer from root rot and perish suddenly.
Many people in Australia regard Rosella as an exotic plant, but it is in fact documented as a native plant, found growing wild in the coastal scrub of the Northern Territories prior to European occupation. It is thought to have been introduced thousands of years ago, either by Indonesian settlers or earlier still by aboriginal people. Today it is an important cultural plant, intertwined with Australia’s early history, and it can also be regarded as ‘bush tucker’.
Rosella also grows wild through the tropics and subtropics of the Indian subcontinent, South-East Asia and New Guinea, with varying strains and growth habits. However recent research indicates its origins may originally be in east Africa and that it may be a prehistoric introduction in much of its current range. In Australia and overseas it is commonly found growing wild on man disturbed sites. In recent years Rosella has been listed as a minor weed in the Northern Territories, Northern Western Australia and Far Northern Queensland.
Don’t think Rosella takes up unnecessary space over spring and summer because the other great thing about this plant is that it produces delicious, cranberry flavoured, young leaves. I add these leaves to salads in summer and surprise guests who can’t believe the unusual flavor. Children enjoy eating these greens because “they taste like lollies”. The leaves are also delicious lightly cooked in a variety of dishes. If you ever visit South-east Asia or the Indian subcontinent you will soon spot this popular vegetable being sold in markets.
I harvest young leaves and shoots while shaping the young bushes to encourage branching, but once the shorter days arrive, minimize removal of shoots and leaves so that the plants can focus on ‘fruit’ production. You’ll soon spot the flower buds appearing between the leaves at each node up along the branches. The new leaves will also change in shape, from being divided to a simple shape. Once the flowers drop, the calyx will increase in size and gradually lighten in colour, and then the individual sepals will pull apart. The best time to pick the ‘fruit’ is when they are fully grown but still soft and tender. However, I have had delicious jam made from older ‘fruit’.
The ‘fruit’ are not all ready at once, so harvesting must occur half weekly to weekly. Many friends of mine put the ‘fruit’ in the fridge or freezer until they are ready to process a batch.
If you look inside the ‘fruit’, by peeling back the sepals, you will spot a round knob. This is the seedpod. In time it will dry and split open, releasing the seeds. I always leave a few ‘fruit’ on my plants and save seed for future use. Selected from the most vigorous and productive plants, you will develop an outstanding strain by doing this each year.
Many people pull out their plants once all the ‘fruit’ are removed. However, a tip I learned from Rosella grower Debbie McGarry is to prune of all the fruiting branches and leave plants in the ground over winter to get a second, smaller ‘out of season’ spring harvest. This is a traditional technique that only works if your site is warm and frost-free over winter. The plants will probably die back and defoliate a little, but will have one last spurt of growth and ‘fruiting’ before they die.
I have a few different cultivars which I rotate each year. This year I grew some of the best Rosellas I have ever grown. I got the seed from well known organic gardener Phil Ryan. Phil is also a keen Rosella grower and last year found an outstanding clone among his plants with larger ‘fruit’ than normal. It certainly is a great clone, one that I will maintain and spread around.
The most popular cultivar grown these days seems to be ‘Early Crop’ or ‘Compact’ and is a smaller, densely branched bush which doesn’t grow too tall. It has quite narrow and deeply divided leaves. This plant is best suited to commercial production.
Occasionally you will come across some older gardeners growing taller varieties. I tend to think these are more productive and space efficient and ideal for smaller gardens. They are also very ornamental when festooned with fruit.
The Thai community grows a strain with broader leaves and smaller, differently shaped ‘fruit’, where the calyx hugs the seedpod. The flowers are blushed pink rather than cream. The Thais grow the plant predominantly for the leaves.
Some 20 years ago there was much more diversity in the plants grown, with notable Rosella clones having black (blackish-red), yellow and white ‘fruit’. I’m hunting for some of these older clones so please contact me if you know of a seed source.
Barbara’s Recipe for Rosella Jam
I’m no expert at making jam and this year’s crop was processed by a friend, Barbara Steiner. Barbara makes delicious jams and shares my preference for flavoursome jams that are not too sweet. The Australian standard seems to be equal weight of sugar and fruit, but too much sugar kills the flavor of any jam.
To prepare rosella ‘fruit’, peel the red flesh from the stem and pod using fingers or a knife. The flesh snaps off the stem quite readily. Remove any damaged or discoloured flesh. Some people use apple corers to cut the calyx from the stem. A traditional tool for this job was made from a sharpened copper pipe and occasionally you see these handmade tools in second hand shops. Retain the seedpods to extract their pectin. Wash the ‘fruit’ and pods and remove any wildlife.
This jam is very quick to make. The most time is spent preparing the ‘fruit’!
… Bon Appétit!
[Jam making photos by Barbara Steiner]
While Rosella is best known as a jam, syrup and cordial, it can also be used in many other ways for its cranberry-like flavour. In savory dishes, it can be used as a couli, chopped and added to salads, in curries, and in pickles, relish and chutneys. For desserts it can be used as a sauce, a jelly, mixed with apples in crumbles and puddings, stewed as a filling for tarts and pies or simply eaten with ice cream. As a beverage, calyxes can be boiled with water to make a cordial, it can be used as a flavouring for spritzers, and marinated in brandy.
Dried Rosella ‘fruit’ makes a delicious tea or tisane. The tea is often sold as hibiscus or rose hip tea and in recent years, has been widely promoted as a tonic to help lower blood pressure.
Of course the classic use for Rosella is to boil whole ‘fruit’ (pod and stem removed) in sugar syrup and bottle. The individual fruit can then be rinsed and added to a glass of champagne or a cocktail for a memorable toast.
While it may be winter and the warmer weather may seem a long way off, now is the time to start working through the seed catalogues and planning what to sow and grow once the weather warms. Rosella seeds are available online from a number of seed suppliers and are relatively easy to grow. Get your orders in now or purchase some seedlings this spring, as Rosella is a rewarding plant to have in the garden. This time next year you could be enjoying your own home grown and home made Rosella jam or making a toast to this culinary treasure!