Arno KingJam of the tropics: growing and using Rosella

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.

Traditional taller growing rosella

Traditional taller growing rosella

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.

The red eyed cream flower, flower buds and fruit

The red-eyed cream flower, flower buds and fruit

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.

Rosella at the Sydney Botanic Gardens

Rosella at the Sydney Botanic Gardens

 

Growing rosella

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.

Reddish leaves and stunted growth indicate poor nutition

Reddish leaves and stunted growth indicate poor nutition

 

Origins

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.

Harvesting

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.

Rosella leaves in a Singapore market

Rosella leaves in a Singapore market

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’.

Note flowering top growth above the leafy bush

Note flowering top growth above the leafy bush

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.

Extra crop

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.

Different cultivars

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.

'Earlycrop' is a popular dense cultivar

‘Earlycrop’ is a popular dense cultivar

Cream flowers on 'Earlycrop'

Cream flowers on ‘Earlycrop’

Note the narrow leaves on this 'Earlycrop' cultivar

Note the narrow leaves on this ‘Earlycrop’ cultivar

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.

Traditional taller growing rosella

Traditional taller growing rosella

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.

Pink blushed flowers of Thai rosella

Pink-blushed flowers of Thai Rosella

Thai type Rosella with broad leaves

Thai Rosella with broad leaves

Thai Rosella 'fruit'

Thai Rosella ‘fruit’

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’!

  1. Place prepared ‘fruit’ in a largish cooking pot and the seedpods in a separate smaller cooking pot.
  2. Cover the seedpods with water, bring to the boil and simmer them for about 10 minutes until soft. This extracts the pectin.
  3. Drain the water off the seedpods into the large pot with the ‘fruit’ and discard the seedpods. Bring ‘the fruit’ to the boil and cook until soft. This takes about 10 minutes.
  4. Weigh the cooked pulp and use approx. 700g of sugar per kilogram of pulp. Best to taste it a few times to ensure there is a good balance of sugar and tartness.
  5. Cook the pulp and sugar mix for about 7-10 minutes or until a liquid sample on a plate wrinkles when running a finger through it. This jam sets very readily as there is so much pectin from the seeds, hence it is necessary to do the “set test” several times at relatively short intervals.
  6. Spoon into previously sterilised hot glass jars. If using narrow necked jars, sterilise a jug as well and fill it with the jam, then pour the jam into the sterilised hot jars.
  7. Repeat procedure for the remaining fruit. Then share your jam with family and friends.

… Bon Appétit!

A bucket of Rosella 'fruit'

A bucket of Rosella ‘fruit’

Washing them!

Washing them!

Ready for the pot

Ready for the pot

Pectin rich seedpods ready for cooking

Pectin rich seedpods ready for cooking

'Flowers' boiling away

Rosella flesh boiling away

Seedpods cooked and discarded

Seedpods cooked and discarded

More pulp to be cooked!

More pulp to be cooked!

A messy job filling the jars

A messy job filling the jars

A start with some lids on

A start with some lids on

A few more jars filled

A few more jars filled

It's 10pm - the last pulp to be cooked

It’s 10pm – the last pulp to be cooked

The result - 19 jars!

The result – 19 jars!

[Jam making photos by Barbara Steiner]

 

Other uses

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!

Rosellas even make great cutflowers - as in this Melbourne florist

Rosellas even make great cutflowers – as in this Melbourne florist

 

 

 

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Arno King

About Arno King

Landscape architect, horticulturist, journalist and keen gardener, Arno is a regular contributor to Subtropical Gardening Magazine. Based in Brisbane, Arno grows a wide diversity of unusual plant species and has particular interests in growing edible plants in creative settings and biological and organic gardening. Brisbane, Queensland

13 thoughts on “Jam of the tropics: growing and using Rosella

  1. helen on said:

    Timely blog for me, Arno! Have just returned from a fortnight in the Kimberleys and saw a huge patch of these – very spectacular! I *thought* they were rosellas but have never seen them growing, nor the fresh “fruit” – they aren’t available in Adelaide though some people do have them, I gather. As I write this, my garden is covered in white hail, and my growing season is quite short, but perhaps worth a try in spring.

    • Arno King on said:

      Hello Helen

      Great to hear from you. I haven’t heard of Rosella being grown in Adelaide, but I’m sure someone there is giving it a go. It might grow best in a greenhouse in your climate. It certainly seems to thrive in our hottest, wettest months.

      I haven’t yet seen Rosellas growing wild in the Northern Territories, but I look forward to going there one day and seeing them as well as the stunning landscapes they have up there.

      I might not have hail, but it is dry, windy and cold here in my garden today. The garden and landscape will change dramatically when the warmer, wetter weather arrives. Winter’s not my favourite time of year.

      Arno

  2. Chantelle Leenstra on said:

    Great to learn that the leaves are edible, and available in some South-east Asian markets. I’ll be keeping a look out next time I travel. Thanks Arno!

    • Arno King on said:

      Hello Chantelle

      Once you recognise them, you’ll see the leaves in markets throughout South East Asia and the Indian Subcontinent. In tropical areas they are available year round. You might even be able to find some restaurants serving dishes using the leaves.

      Arno

  3. Heather on said:

    Thanks for the memories. I remember while living in Darwin 50 years ago going with friends on a Rosella picking picnic, then making the delicious jam at home. Unfortunately I think the Canberra summer is too short to try to grow them.

    • Arno King on said:

      Hello Heather

      what a wonderful memory to have. I’m sure these picnics and Jam making session were very social events.

      I suspect Rosella plants will not grow well in your area due to the limited growing season and general climate. But take heart, you can grow delicious fruits such as Raspberries, Blackberries and Cherries which make some of my favourite jams.

      Rosella jam is also now available in shops in Qld and the NT so you can also buy a jar to take home next time you visit.

      Arno

  4. I’m looking forward to my bottle 🙂 🙂

    • Arno King on said:

      Hello Paul

      Barbara’s jam is so delicious (particularly on hot toast with melting butter), that I’m going to be rationing my jars of red nectar. I think if I’m careful, I’ll have just enough to make it through to next year.

      However, Its now time for you to prepare a garden bed and plan for a home grown crop and jam making session next year. Its not long now until sowing time.

      Arno

  5. Thanks Arno – lots to chew on in here. Interesting about rosellas being in the NT c/o whoever. The thai version is intriguing as are the edible leaves. Good work. Must get some seed!

    • Arno King on said:

      Hello Stuart

      Yes its very interesting to review the plants that were introduced and grown in northern Australia prior to colonisation. These plants also include rice, greater yam, taro, grain setaria cultivars, tamarind, boab and of course lotus. Many have origins in Asia, but others come farther afield from Africa. In my area there are some ancient Bunya Pines planted well south of their natural distribution and associated with sacred locations.

      There is an uneasy relationship with these plants and many have been classified as environmental weeds for eradication. It has been noted that they conflict with the notions that there was no one here, or that Aboriginal people were nomadic or did not cultivate plants, and therefore the land was available freely to the European settlers.

      And of course, we mustn’t forget the Torres Straight Islanders, particularly those in the northern Islands who have strong horticultural traditions and grow a wide diversity of plants, much like the New Guinea Islanders to the north.

      Now some of our notions are being challenged, particularly in northern Australia where genetic studies have started to reveal the intriguing origins of many of these fascinating plants.

      I hope we will one day celebrate these unique cultivated plants, have pride in our heritage and showcase them in our private and botanic gardens. This might preserve them for future generations as many are uniquely adapted to local conditions and have very interesting horticultural traits.

      Arno

  6. Helen on said:

    Loved your story Arno, and learned a lot. Thank you.

    • Arno King on said:

      Thanks for the kind feedback Helen

      Climate permitting, I hope this might encourage you to grow some Rosella plants in your garden this spring.

      Arno

  7. Tinuade Gbadamosi on said:

    Thank you for sharing. I would love to plant it in my garden

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