The Herbal Houseplant Nobody Knows

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Cardamom (Elettaria cardamomum). Photo: laidbackgardener.com

I’ve been growing cardamom (Elettaria cardamomum) as a houseplant for so long (probably about 30 years), I can’t even remember where I got my original plant. It was undoubtedly a division someone gave me. And it’s turned out to be one of the most stalwart houseplants I grow, nearly unkillable. 

Cardamom pods with seeds. No, your plant won’t produce these! Photo: Cardamom Days Food

That said, I’ve never been able to get it to bloom and produce the cardamom seeds used in Thai and Indian cooking. You probably know it as an ingredient of curry and Middle Eastern spice mixes. Or from Scandinavian pastries. 

And I’m not alone in not getting mine to bloom: check it out on the Internet. Everyone succeeds with the plant and gets foliage galore, but no one ever seems to get their plant to bloom. Not indoors in a temperate climate, at least.

What Is It?

Cardamom, also called true cardamom or green cardamom (E. cardamomum), is a tropical plant in the ginger family (Zingiberaceae). As mentioned, it’s usually considered the “true cardamom,” although other related plants (notably black cardamom [Amonum subulatum] are also used as spices, while false cardamom (Alpinia nutans) imitates the scent, but its seeds are not used as a spice. 

It produces upright arching green stems with alternate leaves in two ranks. They’re quite lance-shaped and quite narrow, with a distinct drip tip. They’re also highly and deliciously aromatic. Just running your fingers through them brings an effusion of tropical sensations: definitely something to do on a winter day when you just can’t stand the cold anymore!

Cardamom in its native India is huge evergreen herb. Photo: Rainer Haeßner, Wikimedia Commons

In the tropics (it’s native to southern India), it’s a whopper of a plant, reaching 2 to 4 m (6 to 13 ft) in height, but it’s much more modest indoors: a height of about 60 to 120 cm (2 to 4 feet) is average.

The creeping seed stalks of cardamom… in the tropics, of course, not indoors! Photo: AmonHeijne, Wikimedia Commons

And in the tropics, under hot, humid conditions (USDA hardiness zones 10 to 12), it also blooms and produces green seed capsules on a separate, ground-hugging stalk: they contain the spice used in cooking. Indoors … forget it. Flowers never appear: it will forever remain a foliage plant.

Underground, a mass of rhizomes forms, producing further stalks. No matter what size pot you put it in, it will fill it. Right to the edge. 

Can You Use the Rhizomes?

Fair question. And the answer is: not that I know of. But you can use the leaves. 

They impart a fresh, sweet taste somewhat like cinnamon and to drinks, sauces, fish, seafood and meat dishes. 

Vodka infusion. Photo: http://www.koppertcress.com

For example, crush the leaves and put them in a bottle, then pour in gin or vodka and let them infuse for a few days. Then use the gin or vodka to make cocktails with a delicious cardamom scent and flavor.  You can also make cardamom tea by soaking a leaf in boiling water. Or stuff some leaves inside a chicken to give a touch of the exotic to a everyday meal. In Trinidad, the leaves are used to make curries.

Easy to Grow

Cardamom indoors. Photo: Laidbackgardener.com

This plant seems to thrive no matter where I put it: in sun or in shade. Since sun is at a premium at my place, the poor plant always ends up stuffed under the shelves of my other plants for the winter, simply because it can take it and few other plants can. 

In the summer, but only after things warm up (it does not like the cold: temperatures below 10˚C/50˚C are verboten!), it goes outdoors, again in a shady spot … but don’t feel sorry for it there: shade outdoors is much brighter than shade indoors and it will put on much of its yearly growth while outside!

Summer rains will clean the leaves. Photo: davisla.wordpress.com

Summer rains remove any dust from the leaves. If you keep yours indoors all year, you could accomplish the same thing by giving it a shower of warm water once in a while.

Water it regularly and deeply, as soon as the potting mix is dry to the touch. Its leaves start to roll up when the soil is too dry: consider that a warning sign and give it a thorough soaking. And don’t let that happen too often: it’s clearly happier when kept more on the moist side. There is no dormant period. 

You can fertilize it lightly using the fertilizer of your choice, logically during the summer, but you’ll soon realize it doesn’t react much to fertilizer. 

You can also repot your cardamom during its spring to summer growing season. I usually take advantage of repotting, which I do every 3 or 4 years, to divide it and so give it more space, offering the divisions to friends and neighbors. That’s also a good time to do a bit of a cleaning, removing the older stems and leaves that have turned brown (no leaf lives forever!). They’re not too noticeable from above (they shrink back as they dry, so are largely hidden by the living leaves), although you will notice them if you look at the plant from the side. 

So far, mine has never had any kind of disease or insect problem. Of course, its scent, so delicious to human nostrils, was originally designed as a repellent, to chase away hungry insects and herbivores. And none of my pets has ever munched on it, not even my various cats. And no, it is not poisonous.

One Weakness

Cardamom’s only flaw is that it does love high humidity, so my plant room (the most humid room in the house) is where it overwinters. 

Some people mist the leaves, but that’s a waste of time. Photo: amazon.com

If the air in your home is dry, a common occurrence at that season, the leaf edges can dry out. You’ll see recommendations on the Internet to spray it to increase the humidity, but that is, of course, a waste of time. (See Horticultural Myth: Misting Your Houseplants to understand why.) You might want to put it on a pebble tray during the heating season, or run a humidifier. Or stuff it into a clear plastic bag for the winter if things are really desperate. 

Again, the humidity given off by the other plants in my plant room ensure that the leaves don’t suffer. It would also love a bathroom, where you can use it as a living room freshener by running your fingers through the leaves.


Cardamom is basically an easy-to-grow foliage plant with the advantage of sensuously tropical-scented foliage. You can probably find plants or seeds (a bit difficult to germinate) at a herb specialist near you!

Edible Houseplants

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Coffee fruit - Coffea arabica

A coffee plant (Coffea arabica) will produce it’s colorful “cherries” indoors.

Question: Are there any houseplants that are both edible and attractive?

Clecio Turgeon

Answer: There are many tropical plants that are both easy to grow indoors and give us something to nibble on or to add to our recipes… but you won’t find many among the most common houseplants we grow. Most “everyday houseplants” are either not considered edible or are even poisonous. The latter group includes such popular plants as philodendrons, dieffenbachias, oleanders and most euphorbias. You don’t want to eat those!

What follows is a description of some the more interesting edible houseplants.

 

A Growing microgreens on plastic white cup

Micro-greens aren’t really houseplants.

Plants Dropped From the List

I eliminated from the get-go certain plants that I just don’t consider to be houseplants. For example, I didn’t include most of the herbs brought indoors in the fall to grow over the winter, as in my opinion they are not really houseplants and in fact really struggle to survive indoors. You really couldn’t grow them indoors all year.

Nor did I include herbs and vegetables that are sown indoors with a view towards a quick harvest of fresh foliage: sprouts, micro-greens and baby vegetables, for example. Again, in my book, they may be indoor edibles, but they’re not really houseplants. Likewise rooted carrot tops, sprouted sweet potatoes or celery bases sitting in water. They just aren’t houseplants to me.

There are also a few poisonous plants that are edible only after they’re given some kind of special treatment, like cooking, soaking, pounding or being reduced into powder, such as taro (Calocasia esculenta) and variegated manioc (Manihot esculenta ‘Variegata’). I didn’t think it was a good idea to include potentially dangerous plants in a list of edible houseplants, as some readers might skip the “fine print”.


Everyday Houseplants That Are Edible

Here are the few common houseplants, ones readily found in almost any garden center, that just happen to be edible.

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Calamondin orange (X Citrofortunella microcarpa)

Calamondin Orange (X Citrofortunella microcarpa, syn. X C. mitis)
This is the only citrus commonly offered as a houseplant. It is inevitably already in fruit when you buy it and you just need to give it good conditions (especially, strong light) for it to continue it bloom and produce abundantly. The fruits are very bitter, but they can be used in cooking, especially in the preparation of marmalades. For suggestions of other less widely available indoor citruses, see Indoor Fruits below.

Chinese Hibiscus (Hibiscus rosa-sinensis)
The flowers are edible and often used in herbal tea. Here’s an article about this plant: The Secrets to Growing a Hibiscus Indoors.

Coffee (Coffea arabica)
Young coffee plants, usually scarcely more than seedlings, can easily be found on the market, but may be 2 or 3 years from blooming… and 5 to 6 years before producing enough beans to make a cup of coffee. Occasionally you find more mature plants already producing their highly perfumed white flowers.

You can actually eat the sweet flesh of the coffee “cherries” that follow or simply clean, roast and grind up the “beans” (seeds) to make a delicious drink.

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False shamrock (Oxalis triangularis)

False Shamrock (Oxalis triangularis, syn. O. regnellii)
The leaves of this popular houseplant can be purple or green, with or without a silvery or pink marking… and they are quite edible, with a sweet/sour taste. This comes from the oxalic acid they contain. However, oxalic acid becomes toxic if eaten raw in large quantities, so moderate your use. Or cook the leaves before use. Just to reassure you, remember that spinach, which we routinely eat, also contains oxalic acid and is also toxic if eaten raw in excessive quantities. As they say, the poison is in the dose: eating a few leaves will not harm you.

Ornamental Pepper (Capiscum annuum and others)
All peppers are edible, even the ones sold as ornamental plants. Be forewarned though that ornamental peppers are hot peppers, indeed, very hot peppers, generally stronger then jalapeños.

You may sometimes see them bearing the label “unfit for human consumption”, though. Why is that? It’s not because the fruit itself is poisonous, but because it was treated with an insecticide that is potentially harmful to humans. Organic gardeners will consider the fruits spoiled for life; others can wait a few weeks, then rinse the fruits before eating them. Both can harvest the seeds and grow them to produce fruits totally safe to eat in the second generation.

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Ornamental pineapple (Ananas comosus cv)

Pineapple (Ananas comosus)
There are several varieties of ornamental pineapple, for example with reddish foliage, variegated leaves, colored fruit, etc. And all produce fruits which, although they’re often smaller than commercially grown pineapples, are still edible.

Besides ornamental varieties of pineapple, you can also buy a fresh pineapple and root its crown. And yes, it will eventually produce an edible fruit.

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Lemony rose scented geranium (Pelargonium graveolens ‘Lady Plymouth’)

Scented Geranium (Pelargonium graveolens and others)
There are a multitude of varieties of scented geranium with an incredible array of scents: lemon, rose, coconut, apple. peach, strawberry, cloves, etc. In addition to rubbing the foliage to release their scent, you can use their leaves in cooking to impart a delicious aroma to your meal. Richters (Canada) offers an especially wide choice: more than 70 varieties of these highly perfumed plants!

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Swiss cheese plant (Monstera deliciosa)

Swiss Cheese Plant or Monstera (Monstera deliciosa)
Often mistaken for a philodendron (which is a close relative), the monstera, with its huge, deeply-cut leaves, certainly makes an impressive houseplant. When it reaches maturity, which can take many years, it will flower indoors, producing a white inflorescence recalling a calla lily. And the flower is followed by a sweet-tasting fruit, which is the reason for the botanical epithet deliciosa. The fruit can take 11 to 12 months to mature, and doesn’t change color too visibly at maturity. So how do you know it’s ripe? When the green scales that cover it begin to drop off, it’s ready to eat.

Note that the entire plant, from its roots to its leaves to its immature fruits, is toxic. Only the mature fruit is edible.

Tea Plant (Camellia sinensis)
Yes, tea plants. although not yet as common as the other everyday houseplants presented here, are found more and more often in garden centers. Here is an article about how to grow one: Homegrown Tea in Your Teapot.


Indoor Fruits

There are hundreds of different tropical fruit trees, all of which could theoretically be grown indoors, but most won’t produce for decades, will become too large to make good houseplants or require really extreme growing conditions. Since they are unlikely to ever produce fruit in your home, I excluded them from my list.

In this group of “forbidden fruits”, you’ll find most of the tropical fruits that can be grown from seeds or pits harvested from the fruits you buy, such as avocados (Persea americana), mangos (Mangifera indica), and papayas (Papaya carica). Of course, if you look hard enough, you may be able to find dwarf varieties of these plants that will produce fruits indoors, but otherwise its best to consider most tropical fruits you grow from seed simply as foliage plants!

What follows are a few fruiting plants that are more suitable for growing in our homes and that really do make good edible houseplants.

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Barbados cherry (Malphigia glabra)

Barbados Cherry (Malpighia glabra)
Pretty pink flowers, bright red cherrylike fruits on a small shrub that fits neatly into most home decors. What’s not to like?

Cacao Tree (Theobroma cacao)

A challenge to grow and not readily found on the market, a cacao tree can still produce cacao beans at home… if you turn your home into a hot and humid jungle year round.

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Key lime (Citrusaurantiifolia) makes an easy-to-grow indoor citrus.

Citrus (Citrus spp., Microcitrus australasica and Fortunella spp.)
As mentioned in the article A Lemon or Orange Tree From Seed?, real lemon trees, orange trees, grapefruit trees, etc. are simply too large and too slow to produce to make good indoor fruit trees, unless you can find grafted dwarf varieties.

Other lesser-known citrus fruits, faster in growth and of a naturally smaller size, make much better indoor plants. This is particularly the case for the Meyer lemon (Citrus x meyeri) which, despite its name, is not a real lemon, the Key lime (C. x aurantiifolia) and the Australian finger lime (Microcitrus australasica). You can sow any one of these and have fruit 2 years later!

Kumquats (Fortunella spp.) too make excellent indoor fruit trees.

Common Fig (Ficus carica)
It prefers to pass its summer outdoors… and has the bad habit of losing most of its leaves during the winter, leading to a rather stark appearance, but the fig tree still quite readily produces figs indoors. Moreover, its foliage is edible too.

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Dwarf banana

Dwarf Banana (Musa spp.)
Even a dwarf banana tree takes up a lot of space indoors (among the smallest cultivars are ‘Super Dwarf Cavendish’ and ‘Truly Tiny’) and also require a lot of heat, humidity and sun to produce fruit. Plus they may take years to produce bananas, but still, most will eventually do so if your conditions are right.

The pink banana (Musa velutina), with pink flowers and fruits, is another small-size edible banana you might like to try, but you’ll have to eat around its large seeds.

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Dwarf pomegranate (Punica granatum ‘Nana’)

Dwarf Pomegranate (Punica granatum ‘Nana’)
This is a miniature version of the rather large pomegranate tree whose fruits are found in the supermarket. It forms a small to medium-sized shrub with orange flowers that will readily produce small but nevertheless edible fruits indoors. Even if you grow it from seed (it comes true to type), it will bear blooms and fruits in only a few years.

Natal Plum (Carissa macrocarpa)

This small thorny shrub with shiny leaves makes a good houseplant and readily produces white flowers and edible red fruits. It is sometimes used as bonsai. Both the stem and leaves, and even the sap, are poisonous. Only the ripe fruit is edible.

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Passionfruit (Passiflora edulis)

Passionfruit (Passiflora edulis)
This vigorous climber will need a good trellis, but can produce its white flowers with a purple halo and its purple or yellow fruits (the color depends on the cultivar chosen) in a sunny spot indoors. There are plenty of other species of passionfruit that do well indoors, but only a few produce edible fruit.

Pitahaya or Dragon Fruit (Hylocereus undatus, H. polyrhizus, H. megalanthus and others)
These climbing cacti take up a lot of space, but bloom fairly easily when they reach maturity (after 5 or 6 years), producing enormous white fragrant nocturnal flowers followed by large red or yellow fruits with white flesh that is dotted with tiny black seeds. This is a good example of a plant you can grow to fruiting size from seeds harvested from fruit purchased in the supermarket. You just have to be patient!

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Fishbone cactus (Epiphyllum anguliger)

I grow a smaller and closely related cactus, the fishbone cactus (Epiphyllum anguliger), with hanging flattened zigzag stems whose very fragrant nocturnal white flowers often give small edible green fruits… but it’s difficult to judge when they are ripe. It too takes years to begin to bloom, but once it starts, it will faithfully continue to do so.

Pixie Grape (Vitis x Pixie® Pinot Meunier)

A dwarf mutation of the Pinot Meunier grape vine which produces fruit all year on a small plant… and its leaves are edible too. It can be grown as a houseplant, but is also hardy outdoors.

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Roselle (Hibiscus sabdariffa)

Roselle (Hibiscus sabadariffa)
This shrub with small yellow hibiscus flowers grows quickly from seed. In fact, you can treat is an annual if you wish. It produces red fruits often used in drinks and jellies.


Indoor Herbs and Spices

Herbs and spices flavor our meals and often have medicinal uses as well. I limited the choice here to varieties that really make decent houseplants.

Bayleaf (Laurus nobilis)
In my opinion, this is the only “classic” herb that grows well enough indoors to make a good houseplant. It will grow indoors for years, eventually forming a tall shrub if you don’t prune it. The leaves can simply be plucked and used fresh as needed.

Black Pepper (Piper nigrum)
This climbing plant produces smooth shiny leaves and long spikes of green berries that turn red at maturity and is not difficult to grow indoors if you can offer good humidity. The berries give black, white or red pepper, depending on the treatment you give them.

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Ginger (Zingiber officinale)

Ginger (Zingiber officinale)
You can readily grow ginger from rhizomes purchased locally. Beware though that the rhizomes offered in many supermarkets were treated chemically or irradiated in order prevent them from sprouting. There is no use planting those! You need live rhizomes, with buds indicating they are ready to sprout. An Asian supermarket should have some.

Just push a section of rhizome into a pot of growing mix and water: a green rather bamboolike plant will soon start to sprout. Over time, the rhizome will spread and you can then harvest and eat any surplus. Don’t expect this plant to flower indoors, though: it almost never does.

Other spices in the ginger family also produce edible rhizomes and likewise make excellent houseplants: galanga (Alpinia galanga), turmeric (Cucurma longa) and cardamom (Elettaria cardamomum) are only a few examples.

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Society garlic (Tulbaghia violacea)

Society Garlic (Tulbaghia violacea)
This is a bulbous plant with grasslike leaves and small pink trumpet flowers. The whole plant smells like garlic. If you use the edible leaves and flowers in your cooking, they’ll give the meal a garlicky scent, but without the bad breath that follows eating real garlic. The name society garlic come from the idea that you could safely eat it before attending polite society functions.

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The variegated forme of Spanish thyme (Plectranthus amboinicus ‘Variegatus’) is probably more popular than the species.

Spanish Thyme or Cuban oregano (Plectranthus amboinicus)
This plant is neither a thyme (Thymus spp.) nor an oregano (Origanum spp.), but rather a tropical plant closely related to the coleus (Plectranthus scutellaroides, syn Solenostemon scutellarioides and Coleus blumei). It’s a very popular herb in tropical countries where its thick leaves lend taste of oregano to cooked dishes. It’s very easy to grow.

Stevia or Sweetleaf (Stevia rebaudiana)
Increasingly popular for its sweet leaves that give dishes a sugary flavor without adding calories… and it makes a decent houseplant.


Indoor Vegetables

There aren’t many plants you could call vegetables that also make good houseplants. I could only think of the following two:

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Malabar spinach (Basel alba ‘Rubra’)

Malabar Spinach (Basella alba)
An ornamental climber with mucilaginous leaves used to replace spinach, Malabar spinach is often grown in hot climates where real spinach doesn’t grow well. The species itself produces green stems and white flowers, but B. alba ‘Rubra’, perhaps even more commonly grown, has reddish stems and pink flowers. Both are very easy to grow.

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Spineless nopal (Opuntia ficus-indica ‘Burbank Spineless’)

Nopal or Barbary Fig (Opuntia ficus-indica and others)
Many different opuntias are used as nopals, but Barbary fig is the most common one. This cactus with flattened pads does produce edible fruits called Barbary figs when grown outdoors in a hot, dry climate, but indoors it rarely blooms, let alone produces fruit. It made it onto my “edible houseplant list” by virtue of its edible pads.

Nopal is the name commonly used in Mexico for the pads treated as a vegetable. You’ll probably need several plants if you want to start harvest nopals, as the plant is very slow growing. You have to singe off the spines before you eat the pads… or use spineless (or nearly spineless) cultivars like ‘Burbank Spineless’.

This plant will need full sun to do well indoors. And yes, you can root a pad from the grocery store to start a new plant.

Where to Find Edible Houseplants?

Many of the plants above are not found in just any garden center, so here are few places where you might want to look for them on the Web.

For herbs and species, try Richters, a Canadian company that ships to the US and probably offers more choices of herbs than any other.

For unusual fruits and vegetables, try Flora Exotica, also a Canadian company that ships to the US, while Top Tropicals is an American company that ships to Canada and many other countries worldwide. Logee’s, in the US, is a good source for American readers, but no longer ships to Canada.

For European readers, try AlsaPlants. If you know of any other good mail-order sources of indoor edibles in Europe, let me know and I’ll add them to this text.

Bon appétit!