Time to Winterize
by Michael Louie (San Mateo, Ca.)
Re-potting and Potting Up
by Michael Louie (San Mateo, Ca.)
Seed Cleaning
by Tom Steppe (Concord, Ca.)
Connoisseur's Corner: Senecio ballyi
by Carl Frederick (San Anselmo, Ca.)
The Root Succulent Mesembs
by Carl Frederick (San Anselmo, Ca.)
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Time to Winterize
by Michael Louie (San Mateo, Ca.)
Yes folks it is that time of year when Summer has gone away and Autumn brings uncertain spells of heat with intermittent blasts of cold air. It won't be long before the shortened days coax our plants into dormancy and the rains will start. The combination of wet and cold is never a good one for succulents and many of us resort to bringing plants into cold- frames, greenhouses, indoors or use covers to protect plants from the wet-cold combination.
The first thing to do to get ready for winter is pest control. Be sure that your plants are healthy and not infested with root/crown mealy bugs, scale, aphids, mites, cyberkids, Sciara flies, white fly and other pests that could devastate a greenhouse. Use systemic and/or surface insecticides at least 3 weeks before bringing them into an enclosed area because these chemicals are far less dangerous to humans and pets after 2-3 weeks. Remove all weeds from potted plants and change soil that is heavily infested with Sciara fly. The last thing you want are weeds that produce seed in the close, dense confines of the Winter rest area spreading their baneful progeny to spoil the next growing season.
Stapeliads have a very difficult time making it through the winter unless they are pest-free and have a thorough regiment of fungicide treatment (spray once every 2 weeks with Ortho Funginex). Stapeliads need to be kept somewhat dry and warm over the winter. Leafy caudiciforms such Adenium, Adenia, Pachypodium and cucurbits should not be fed any longer with watering gradually cut back to encourage leaf drop and dormancy. Be sure to look out for mites and mealy bugs that thrive under the leaves in a low humidity environment. A deep watering with a systemic insecticide (like Marathon) and a light spraying of malathion will keep the critters at bay. Be careful not to use too high of a concentration of insecticide since the formulation surfactants can cause damage to stem tips. Take special care to avoid physical injury to the body and stems of plants because bacterial or fungal infections can be disfiguring and lethal during this time of year. Leaf damage is not critical for plants that shed them during this season.
Finally, flowering succulents, such as mature cacti and Adenium should be given a small portion of 0-10-10 (blossom builder) during the final waterings to encourage dormancy, to toughen up roots and to ensure a large crop of bloom during the next growing season. Be careful not to use too much 0-10-10 on caudex plants since an excess of phosphorus can encourage fungal attack. Be sure that you have heavy plastic tarps handy to cover or insulate plants in case of a cold snap. The meteorologists are predicting a "mild" but wet winter primarily due to global warming. El Nio and La Nia are not expected this winter. Remember to take notes and learn from experimentation and others' mistakes.
Winter Grower Plants and 'Autumn Burn'
Many mesembs that have been dormant during the summer are active now. However, if you are moving your winter-growing plants out from a protected dormancy area, be wary about Autumn burn. During the heat of the summer, the San Joaquin Valley (about 35 miles directly inland from the SF Peninsula), heats up to 95-100 F during the day. In the evenings, the Valley cools rapidly creating an upward stream of convection. This stream pulls in cold air from the Pacific Ocean that causes condensation of high altitude humidity and the formation of thick high-elevation fog. This fog travels quickly from the western coast inland but dissipates as it approaches the heat of the Valley and vaporizes away. En- route, the daily fog keeps the SF Peninsula cool and shaded for the greater part of the summer. As the Valley cools, the fog curtails and the shading is gone. The increase in heat, light and UV rays can cause burn.
Plants that are not accustomed to the increased light intensity may scorch during the sudden bright hot days. Use shade cloth to slowly acclimate plants until the conditions no longer pose a threat (mid-November). Conophytum should be tearing through papery sheaths and can be misted regularly to encourage growth. Their flower buds look like little inverted cones poking out from a central dimple or leaf crevice--they open during the late part of the afternoon. Crassula, Echeveria and Dudleya are also growing now and fungus tends to be the culprit this time of the year. Use a topical spray (Funginex) sparingly during shady days at least once every two weeks to keep fungus at bay. Monilaria and Mitrophyllum show new signs of turgidity and green color at their extremities. These plants would all benefit from adding a sparse amount of fertilizer into the water you use for misting. Be careful not to apply too much fertilizer because plants that are not fully active will not absorb the food leaving nutrition for microbes and algae. Also, a heavy build up of fertilizer will leave a permanent, unsightly crusting of salt.
Pelargonium, Tylecodon and Othonna should also be waking up. New leaves and/or inflorescence are starting to emerge. Look out for aphids which the ants spread in a desperate attempt to "farm" honeydew before the weather becomes wet and cold. Snails and slugs seem to love the young leaves of Othonna and Tylecodon like a fresh autumn salad-use a liberal dusting of metaldehyde (Correy's Snail Death) at least six inches around these plants. Many growers in the SF Bay Area have found that these winter growers thrive in our natural rain cycles and can be grown without any overhead protection. Remember to feed lightly when the sunlight is strong. Happy Autumn!
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Re-potting and Potting Up
by Michael Louie (San Mateo, Ca.)
First of all, what is the difference between these two practices? Re-potting is when you take a plant out of its container, gentle remove the old soil, debris, dead roots in exchange for fresh growing medium. Re-potting is something that you must do to keep a plant healthy since it is an opportunity to remove any built up toxins that water cannot flush away. Also, dead, decaying roots and other debris that may encourage bacterial and/or fungal colonization is removed. Re-potting is always a stressful event for the plant and the horticulturist since it is an extremely intrusive technique. Many of the fine root hairs and small feeder roots are damaged or broken off, and these "open injuries" may be an opportunity for an infection to occur. The horticulturist generally feels nervous until the plant gives signs of growth again.
Re-potting should be done every other year or once every three years depending on how well the plant grows in the medium ("soil") the horticulturist gives it. A lot of the small liliaceous plants: Haworthia, Gasteria and Aloe benefit from re-potting every 1-2 years since they produce a lot of roots and a build-up of organic matter in the soil proves to be toxic to the plant. Many Euphorbia, Tylecodon and Cotyledon benefit from repotting every 1-2 years as well. Crassula are generally easy plants to grow the first 1-2 years but if they are not re-potted or stem/leaf cuttings rooted to make new plants, they can languish and suffer great set-back. A few years ago, one of our own members, Paul Heiple, wrote an article on how some of the stemmed mesembs can start to die at the center of a stem and the necrosis spreads outward eventually killing the leaves and meristem of the plant. He called the phenomenon "MesAD" to stand for Mesemb Atrophy Disease. The causes for MesAD are not clearly understood but the best way to salvage the ailing plant was to take stem cuttings at first sign of the disease and re-root them. I have found that MesAD happens more frequently if I do not re-pot my stemmed mesembs every 2-3 years. The stemless mimicry mesembs (lithops and conos) seem to be more resistant to MesAD and can survive in the same pot for 6-7 years.
Potting up is a technique where a plant is carefully taken out from its growing container and put into a larger one where more soil can be added. This gives a plant more "root room" to expand into thus encouraging a plant to continue to grow. The dangers associated with potting up are that the plant is still living with the old soil, debris and toxins that persist. Furthermore, the roots may be stressed from being pot-bound (crowded) or wrapped concentrically so that the roots choke each other as they continue to grow. And finally, the added new soil absorbs moisture and dries out at a different rate as the old soil causing further problems. The benefit to potting up is that the practice is non-intrusive, minimizes root trauma and plant injury. The plants that benefit most from potting up are the ones that produce a low density of roots but grow very quickly or those plants that do not "turn-over" roots at a high rate. These include Echeveria, Sedum, Aeonium, Sempervivum and many cacti.
Experience will prove that both techniques, re-potting and potting up, are needed depending on the length of time a particular plant has been in a container, how well and how much a plant has grown in that container. An unhealthy plant with a soil-born infection (fungi, bacteria) or infestation (root mealy, Sciara fly...) can benefit from re- potting but special care must be given to remove much of the old soil and effectively ridding the roots of the pest. The plant should not be over-watered or potted up into a larger container that increases the time it takes for the soil to dry out. Only after the plant recovers and begins to thrive again should it be potted up into the larger container.
As a general rule, if I have to change the soil for a plant that is sick or is going into dormancy, I will re-pot. If an actively growing, healthy plant still has good soil and has out-grown a container, I pot up. Finally, if a plant has languished from being in a container that is too large and dries too slowly, I change the soil and pot down (use a smaller container). It can also take many years to understand how a particular soil mix works in your microclimate. Experience and experimentation will be the key to your success and save you from becoming a nervous 'psyduck' sleeplessly worrying about how a plant will fare under your care.
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Seed Cleaning
by Tom Steppe (Concord, Ca.)
This is the first installment of a series of articles that I am writing describing the techniques that I learned about seed cleaning.
First let's answer some obvious questions: Why do we need cleaned seed at all? One answer becomes clear when you start with a shopping bag of dried seedpods...and end up with a tablespoon of very small, cleaned seed. Another reason becomes very clear: to plant seedpods alone would be very inefficient. You might never know what to expect in germination because the pods may be empty. If you get germination from pods, all the plants would be crowded into a very small space, needing separation or requiring survival of the fittest. Another reason is not so obvious: leaving seed in the pod invites fungal rot. The seedpod is usually rich in moisture for a while after maturation. Separating the seed from all this moist material and drying it a little makes the fungal rot that seedlings are susceptible to (black rot) easier to deal with. The seeds are dry, stable to store and fungal growth is somewhat discouraged. Another not-so-obvious reason is that the seeds of many xerophytic plants need an outer layer of dry tissue to prevent the inner tissue from drying more quickly. Many woodland plants, California natives and xerophytes benefit from cleaning and drying for these reasons.
My adventure in seed cleaning at the University of California Botanical Garden at Berkeley began with an advertisement in the December, 1999 UCBee following a successful field trip into Humboldt and Del Norte counties by Holly Forbes, Roger Raiche and Chris Carmichael to collect California native plants. "If you would like to participate..."
That is how this adventure began. I called Holly Forbes, the curator, who put me in touch with Bibi Chapman. I met Bibi in the seed cleaning room and got an orientation with a bag of Alstromeria aurantiaca. I ground and sieved the first few handfuls of material from the top of the bag and got a few seed. Then Bibi told me a little trick: go for the bottom of the bag. Lo and behold: the seedpods had dried while sitting on the shelf and most of the seed had fallen to the bottom. Now you must understand that A. aurantiaca seeds are about 2 to 3 mm in diameter round, brown and rather hard. The grinding, sieving and winnowing went well, Bibi's advice was important.
A few weeks later I was a little more humble. The species I remember was Mimulus cardinalis (Monkeyflower). I was in for an education. Mimulus seeds are minute, just barely visible with a 7X power hand lens and repeated attempts with the grinding, the sieving and the winnowing gave frustratingly few cleaned seeds. Each pass got them a little cleaner, but progress was slow. I came to find after a few months that Mimulus is a little more typical.
Dust Warning*Dust Warning*Dust Warning*Dust Warning
Dust Warning: Although hand cleaning itself doesn't generate much dust, the grinding, sieving and winnowing that I described can generate enormous amounts of very fine dust. A well-fitting dust mask will help somewhat, but good ventilation is a requirement. Outdoor locations or vent fans to the outdoors will be required.
The most rudimentary of steps toward cleaning is the first step: hand cleaning. Crush a seedpod in your palm over a pie tin. If crushing doesn't work, you may need to dissect the pod with a razor blade, knife or scissors. Now, inspect the resulting debris with a hand lens and you see a few of the little 'jaspers' before you begin crushing in the thresher box. The more genera you clean, the more amazed you will become about nature's variety. It is quite easy to grind your seed into flour and 'eggshells'. If you know what you're looking for, you make the process easier for yourself.
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Connoisseur's Corner: Senecio ballyi by Carl Frederick (San Anselmo, Ca.)
"Senecio, Senecio, who for art thou, Senecio?"
After reading about Senecio ballyi in Miles Anderson's The Ultimate Book of Cacti and Succulents, I started keeping my eyes open for one. The plant has two different growth forms, strictly vegetative with big leaves on short stems and longish flowering spikes with scale-like leaves about an inch long terminated in orange flowers. Finally I found the plant offered by Arid Lands and I bought one. It appeared to be in the flowering phase. The plant consisted of a single stem with alternate leaves and one day it just started shooting towards the sky with a couple flower buds at the end. The flowers seem more typical of the genus Kleinia (rather than the remaining succulent plants in the alternate all- encompassing genus Senecio but that's another story), many packed into the composite flower head, the capitulum. A difference from other kleinias that I grow is that the S. ballyi capitulum spreads more widely than the species K. picticaulis, K. saginata or K. pendula. Or it may have been a matter of the S. ballyi flowers being jammed right up against the top of the greenhouse by the long inflorescence, subjecting them to much greater heat. In any case, they composed a beautiful volumetric orange fan.
So all is understood, right? Wrong! Steve Jankalski, amateur plant researcher and recent contributor to the CSSA Journal (on Euphorbia), has told me that my plant is actually S. nyikensis var. hildebrandtii, and that this plant in cultivation has only been confused with S. ballyi. Turning to Rowley's Succulent Compositae, we find that S. ballyi has been relegated by him to the discard pile and given the status of either not in cultivation, or inadmissible due to nomenclature. Meanwhile he does list S. nyikensis var. hildebrandtii and it seems to describe my plant, except for flower color which he describes as bright red or deep pink...Hmmm. There is another plant that Rowley illustrated in both vegetative and floral growth and it looks very much like my plant--it is described only as Senecio sp. nova.
Finally, in desperation I checked Jacobsen's Lexicon of Succulent Plants to find S. ballyi and not S. nyikensis var. hildebrandtii (although there is a S. nyikensis and a S. hildebrandtii)! His descriptions of both S. ballyi and S. nyikensis appear to fit my plant pretty well. I'm flipping a coin and, as the redoubtable Prof. Rowley would say, "awaiting further enlightenment!"
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The Root Succulent Mesembs
by Carl Frederick (San Anselmo, Ca.)
To the lovers of caudiciform and pachycaul (c/p) succulents, the mesembs are famous for two species: Trichodiadema bulbosum and Mestoklema tuberosum. The former typically has a napiform tuber (I think) but will form a much-branched tuber if grown from cuttings. M. tuberosum grows thick branched roots that have a shiny epidermis and both can be raised above ground level for ease of contemplation. Mestoklema also contains M. arboriforme that apparently grows much larger than its cousin.
Rowley mentions only one other, Phyllobolus resurgens, a plant with thickened rootstock and which dies right back to the ground at the end of the growing season. There are however, many other mesembs that are aching to qualify for c/p status. One common plant which I grow is Delosperma napiforme (formerly Mestoklema macrorhizum) which has the turnip root syndrome. Apparently there are other species of Delosperma sp. that can be confused with Mestoklema sp., they too have tuberous roots.
There are at least 23 other genera of mesembs that possess species that have thick, fleshy or tuberous roots. Perhaps the best known is Aloinopsis sp., the most common example being A. schooneesii which has a thick rootstock from which sprout little green toe-like leaves. The other species of Aloinopsis all have similar rootstocks. Unfortunately, if the rootstock is raised for effect, the plant will try to draw it back down underground. Other genera with large or interesting rootstocks are: Caulipsolon, Saphesia, Nananthus, Ebracteola, Marlothistella and Ectotropis. I haven't grown them but am very interested in the bunch-of-carrots rootstock of Marlothistella, the large, prominent rootstock of Ebracteola and the smallish carrots of Ectotropis.
A different type of plant is Chasmatophyllum, which can be propagated from its rhizomatous roots. And then there's Saphesia with a tuberous rootstock that is capable of resprouting after fire has consumed the aerial portion of the plant. As mentioned, the thickened roots of A. schooneesii will not long tolerate being raised. It is currently unknown (by me!) whether the other genera would be equally reticent about having their private parts put on display.