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Fat Plants -- Plantes Grasses
Yearbook 1980 By: Anne Ginns Back to the web versionRecently we spent a year abroad. Our house, with some plants amongst the furnishings, was let for the duration. Upon our return I found one geranium, one bromeliad and all of the succulents had survived the reign of the blackthumbed tenants. The durability of succulent plants is just one of their virtues, albeit an important one, especially for people who like to take long vaca,tions.
My interest in succulents began through my association with the late George Kalmbacher, taxonomist at Brooklyn Botanic Garden. His enthusiasm for these masterpieces of evolution was infectious. He enhanced the Garden's notable collection, bringing back specimens from his frequent travels. Some of the succulents are very "collectable" and a frustrated fancier can succumb to snitching when he's exhausted the legitimate sources of supply. (Note the decimation of sempervivums in the rockery of the Expedmental Farm.) For this reason fine succulent collections like those at Montreal Botanical Garden are often shown behind bars or glass. Although a born collector, space limitations keep my interest in succulents from getting out of hand.
My current interest is flowering succulent members of several plant families, namely some Senecios of the daisy clan and Stapelias of the milkweed gang. Senecios are the weirdest group. Some look like ivy, some resemble chains of beads and another masquerades as a Stapelia. The only way a botanist can be sure which plant family owns them is to wait until they bloom. They must have given plant explorers a few surprises! Right now my "bead necklace" Senecio rolyanus and my "candle plant" S. articulatus are blooming. The small heads consist of disk flowers which soon go to seed like a tiny dandelion puff. The former blossom has a delightful scent of cloves. The latter flower smells just like fresh cow manure! Most Senecios are so easy to grow, I suspect they are weeds in their native lands.
Reams have been written on succulent culture. There is plenty of conflicting information. Contrary to what a recent magazine article suggests, I find succulents (admittedly the more common types) very easy to raise. The only "difficult" group I've encountered are the "living stones", Lithops, Pleiospilos, Conophytum etc. These mimicry plants represent the extreme of succulence. They have very definite resting periods during which water must be withheld. They also require full sun. Watering is not a problem with most succulents as long as the soil is well drained. Rather than succumbing to overwatering, with proper warmth and light, many succulents will show rank growth which may destroy their "character". Last year I showed the Indoor Gardeners a Notocactus with moss and a fern flourishing in the same pot. The cactus had a poor root system but it wasn't the least rotten, in fact it was in bloom! This cactus shared a greenhouse bench with a mixture of leafy plants and all received a daily shower as well as plenty of fresh air, sunshine and warmth. With practice, a grower will achieve a balance of light, water and temp. which suits most of a collection.
With the exception of "Crown of Thorns", I keep my succulent collection very cool in winter (night temps. are often SCC). Light is good and watering is according to each plant's needs, usually just enough to prevent withering. Plants setting flower buds are kept moist.
My favorite succulents are epiphytic cacti. Much has been broadcast recently about giving Christmas Cacti a short day treatment like Poinsettias to set buds. This fails to explain why one of my plants, residing in the kitchen where the midnight oil often burns, bloomed for the holidays. I think a cool environment helps initiate bud set.
Various potting mixes, usually heavy on materials to promote good drainage are recommended for succulent culture. I find they'll even grow in straight vermiculite if adequate fertilizer is provided. My plants get 20-20-20 during the summer.
Succulents are easy to propagate from seed or cuttings. I root the latter in damp vermiculite.
Insects and diseases are less of a problem with succulents than with other houseplants. The pests I occasionally deal with are attacks of aphids on tender growing tips. These are easily washed off under a faucet. Root mealybug is more difficult to detect and control. For this reason I don't use perlite in my soil mixes. If a plant fails to thrive, tip it out of its pot and check that there are no white particles clinging to the roots and sides of pot. If there are, dust the whole rootball with diazinon, (Kerrydust). Separate saucers for each plant check the spread of this pest. "Above board" mealybugs trouble some growers. Clean them off with an alcohol swab. Use caution in applying pesticides to succulents. Crassulas, especially, are very sensitive and may be killed by the "cure".
Tender succulents won't tolerate freezing temperatures. There are hardy types that will let you extend your collection in an outdoor rockery. I have an Opuntia from the Badlands of Alberta and numerous species of Sempervivum and Sedum.
A word of warning. Euphorbias contain latex which drips when the plant is injured. Keep it away from your eyes! Opuntia microdasys is a plant I hold in the same respect as Poison Ivy. It has thousands of tiny spines which embed themselves in your skin at the slightest touch. Removal is difficult, you can try transparent tape, sticky side up. Otherwise ,they fester out in a few days. Ouch! This plant should not be a household pet.
Looking up from my desk at a collection of succulents; Haworthia, Gasteria, Stapelia, Jade Plant, Aloe, Crown of Thorns displayed across a long window shelf and backlighted by morning sunshine, I know I'd love these plants for their beauty of form, if nothing else.
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