The other day, my husband and I went to see “The Happening”, a movie about a toxic airborne agent that makes the people in Northeastern United States commit suicide en masse. First the victims become disoriented, then they stop talking and moving, and finally they kill themselves by the quickest (and often most gruesome and painful) way.

(Warning: movie spoiler below. Click here to skip this section)

At the start of the film, the belief is that it’s a bioterrorist attack because it’s hitting the areas with the largest populations. But that theory is ruled out as the incidences increase in frequency and the mysterious pandemic spreads out to towns with much smaller populations. The subsequent theory, which comes from a botanist and seems to be the one the movie is intent on sticking to from that point on, is that it’s the trees, and perhaps some bushes and grass as well, that are causing this apocalyptic event. How? By emitting an airborne neurotoxin that entices humans to kill themselves. Why? Because they’re tired of (and threatened by) humankind’s ecological destruction. And so, they create this toxic defense mechanism as a way of saving themselves, but instead of wiping out the entire human species, which they seem able to do easily, they send out a warning instead by killing a good chunk of people in a concentrated area.

This sample of what can happen if the plants gang up on us is supposed to accomplish two things: 1) scare the crap out of everyone by demonstrating how powerful the botanical world is and 2) scare the crap out of everyone by demonstrating how defenseless people are against the power of the botanical world. Basically, the message is that should the plant world unite (the botanist believes that communication and comradeship between different species is possible) and decide that there isn’t enough room for both humans and plants in this world simultaneously, we’re screwed. Plants rule!

So, the concept is pretty cool, definitely Al Gore’s worst nightmare – and likely something environmental activists might use to promote their cause. But the acting is pretty lame, which you expect since the script is too, and it killed whatever potential there was in making the whole thing work. This was undeniably a b-movie, but not one of the better ones, and maybe not even worthy of the big screen. I personally think it was better suited as a half hour episode on the ‘Twilight Zone’ or on its follow-up series ‘Night Gallery’ that I used to watch as a kid.

In any case, even though the movie won’t be winning any academy awards, I did appreciate the idea of plants shelling out some revenge. And if the plant world wanted to reduce our numbers, what hope do we have? What the heck could we do about it? Reason with them? Destroy the plants, which would end up destroying us anyway? We’re doomed no matter how I look at it. And so, on our way back home from the movie, I thought about the houseplants inside my house and imagined them – and there are many of them – suddenly deciding they weren’t too happy with me. And they could easily – because there are certainly enough of them – form an airborne-neurotoxin-releasing army and do away with me. I figured the ring leader would have to be one of the Dieffenbachias, which are extremely toxic plants to begin with.

But the more I think about it, the more I believe it could be any one of them, because in my house there are a lot of poisonous houseplants that could evolve rapidly and increase their potency. And you really can’t tell which one would stab you in the back if it came to that. Some of the ones that are quite toxic are also very attractive and harmless-looking plants that you’d never suspect of any wrongdoing. For example, who would expect that the nice-looking Spathiphyllum, with the common name peace lily, isn’t peaceful at all? Every part of this shifty plant is toxic, and if ingested, will burn your lips and mouth and possibly cause swelling and blistering. This not-so-peaceful rogue can easily wipe the floor with me by teaming up with all my Sansevierias, Philodendrons, Dieffenbachias and even a couple of Pothos, all of which can cause the same symptoms, some of which will take it one step further and cause vomiting, diarrhea, throat swelling, stomach cramps, and breathing and swallowing difficulties. And once I’m down for the count with all the internal problems, why not add some external ones by throwing in the skin irritations and rashes caused by the Crassula Ovata (Jade Plant) and the Ficus Elastica. I tell you, if my plants decide to form a toxic coalition, it’ll be one hell of a nasty one.

I say watch your back. Even the prettiest plants can cause a lot of discomfort. And that brings me to the plant of the day: the Zantedeschia Aethiopica, better known as the Calla Lily. Good looking plant? Sure. Nice flowers? Stunning. Innocent? No way. The leaves and the rhizomes of this beauty can cause burning and swelling of the mouth and throat, stomach pain, acute vomiting and even diarrhea. It’s a bad, bad plant. Of course, you’d have to digest parts of this plant for this to happen, and which adult in their right mind would do that? None of you, huh? That’s what I thought.

So let’s move on to the care requirements of this plant. If you learn to keep it happy, it won’t have any reason to turn on you. Not unless it hangs out with the Dieffenbachias. They can be a bad influence...


Caring For A Calla Lily

Zantedeschia Aethiopica is a species in the Araceae family, which includes popular sub-families (genera) such as Aglaonema, Alocasia, Anthurium, Caladium, Dieffenbachia, Epipremnum Aureum (Pothos), Philodendron, Spathiphyllum, Syngonium, just to name a few. So this species, native to southern regions in Africa and naturalized in Australia, is obviously in very good company with its much beloved cousins. Although the plant is neither a true Arum nor a lily, it does go by the common names of Calla Lily and Arum Lily, Calla being the more popular of the two – at least where I’m from.

Because of its elegance, Zantedeschia Aethiopica is an extremely popular plant indoors and out. The stylish flowers it produces are essential in many celebrations and are a favourite choice in floral arrangements, especially wedding bouquets. They are also used quite often in vases as cut flowers because they last much longer in water than many other types.

In much warmer regions, the Calla Lily can be grown outdoors year round, but in the cold north where I live, the only way you can enjoy this plant for months on end is indoors as a houseplant. Although it is not the easiest to get to bloom, it is not too difficult to maintain inside the house, therefore it is worth a try. Even without blooms, it makes a nice foliage plant. Perhaps that’s not your intention with Zantedeschia Aethiopica – after all, you have enough houseplants to fill your just-leaves-without-flowers needs – but for those of you that don’t mind either way, below is some basic care info.

The one thing to commit to memory after you finish reading this Hydro Log is that Zantedeschia needs perfect conditions indoors to keep it in tip top shape, which in turn will encourage it to bloom. And one of the most important requirements is adequate light. Choose a spot that provides plenty of light while the plant is actively growing. Bright, filtered sunshine is the preference; early morning eastern or late afternoon western sun is ideal. If you decide to grow your plant year round instead of forcing it to go dormant, you may want to place your Zantedeschia where it will receive a couple of hours of southern sun during the colder months. During the summer, particularly on those really hot days, curtain-filtered sunlight should be fine, although you might want to move your plant a little further back from a southern window to protect it against the heat and possible sunburns.

Speaking of dormancy, the best thing to do is to allow your plant to die back during the winter; this is a good way to coax it back into bloom. To do this, stop watering in November and let the foliage die. Trim away all dead leaves and stems, dig the tubers out of the soil and shake away as much of the medium as possible. Store the tubers in vermiculite or peat moss until midwinter in a cool area where the temperature is about 4ºC - 5ºC (about 40ºF). When February rolls around, repot the tubers, place them back into a warm room with good lighting and begin watering. Leaves will grow quickly and (hopefully) flowers will follow shortly.

Use a fast-draining, airy medium and keep it evenly moist during the period that the plant is actively growing. Good watering habits are extremely important to help prevent rot; if the tubers are grown in compacted, consistently waterlogged soil, they will literally turn to mush and you can kiss them goodbye. If you skip the dormancy phase and continue to grow your plant throughout the winter months, allow the medium to dry a little more but never completely. Grow this plant in hydroculture; it couldn’t get easier with a Zantedeschia Aethiopica because there’s no need to transplant. Simply pot up the tubers in clay pellets instead of soil when you bring them home. Make sure you always keep the water level below the plant or the tubers will rot!

Calla Lily will handle average household temperatures very well but it prefers higher levels of humidity to thrive. If the air in your home is too dry, remedy the situation by adding a humidifier nearby, by placing the plant on a pebble tray filled with water, by double-potting and filling the spaces in between the containers with moist peat, by grouping plants together to form a microclimate with higher humidity or by growing the plant in a room naturally higher in humidity. Feed with a liquid fertilizer every 2 – 4 weeks if the plant is healthy and actively growing in ideal conditions. Wipe the top and bottom of the leaves with a damp cloth or sponge every now and then. Regular grooming will keep the foliage shiny, help the plant breathe better and keep pests at bay, particularly spider mites.



The care requirements for this lovely plant are very few and quite simple; therefore, it’s always difficult for me to resist bringing home a few tubers whenever they arrive at the local greenhouses. Although I wouldn’t recommend this plant as the best choice for indoors, it certainly is a good choice. So, if you do happen upon one that is relatively inexpensive, give it a try; it’s certainly worth the effort.

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