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Observations From The Field

Humidity plays and important part in the health of many cacti and succulents. Although they have a reputation for growing in arid places, one might be surprised to learn that nightly fogs actually provide most if not all of the moisture many of these plants need for growth and seed germination.

Along the coasts of southern Africa and and South America cold ocean currents flow north from the Antarctic. While the land itself seldom receives rain, fog which forms at night, condenses on the plants and seeds. Water often runs off the plant bodies bathing . their shallow roots. In Namibia and South Africa many succulent plants including various species of Othonna, Cotyledon, Sarcocaulon,and Pelargonium are able to thrive because of the fog. Likewise along the coast of Chile, a group of cacti called Copiapoa thrive in the fog zone. As one heads inland from the coastal areas beyond the fog zone, the plants are unable to grow.

At higher elevations particularly on islands fog also is an important factor. As the moist ocean air rises it is cooled and fog develops particularly at night. A rich succulent flora is often found in this zone.

Having visited many such environments I became convinced that a foggy environment in my growing area might be beneficial to my plants. I purchased a fogger at a local nursery that I can attach to the end of my hose. On hot days I mist the plants just enough to wet the leaves and body of my plants. I dont wet the soil. I have observed a remarkable change in many of my plants. They grow faster, produce more flowers and just appear better. One must be careful with this procedure as not all cacti in particular like to be wet.

Other growers I know carry around a mist bottle and mist their plants by hand. You may want to try this and see if your plants dont improve their appearance and health.

By OCCSS Member Gary James

Potting Soil, Water & Food for the C&OS Grower

One sure fire way to start a vigorous discussion among growers of C&OS (Cactus & Other Succulents) is to ask "What should I use for potting mix?" This has been the subject of hours of discussion, hundreds of written words and even a complete issue of the CSSA Journal. Various mixtures and additives are promoted with almost religious fervor. The only consensus opinion seems to be that pumice, where available, is the best aggregate to use as a basis for your mix.

Over the last 15 years, I have grown almost exclusively in pumice-based mixtures. I have used several recipes collected from these discussions and writings, and also experimented quite a bit, -- sometimes intentionally, and sometimes due to lack of some ingredient. As the sum of this experience, I can now offer my recipe for success.

I make up quantities of a basic mix from materials that are readily available locally. This mix provides the most important attributes needed by most succulent plants. It is loose and friable with lots of available space for air and roots. It drains very quickly, leaving air space while still retaining enough moisture to reduce frequency of watering without danger of root hair loss. Ph is usually near neutral at 5.5- 6.5. Here in Orange County, I find it suitable for both outdoor and greenhouse culture and use it for all but the most specialized or difficult plants.

My Basic Mix = 5 parts pumice, 2 parts course sand, 3 parts organic material

Pumice is available locally from Orange County Farm Supply in 2 cf. Bags
  The sand must be clean and hopefully, of assorted sizes. #12 Silica from a building supply store also works and, in fact, is what I usually use.

For organic material, there are lots of choices. These are mine, in order of preference:

*Coir (fiberous material from ground up coconut husks)
LGM or Kellogs Leaf Mold
LGM or Kellogs premium planter mix
Supersoil
Composted redwood

*I prefer to use 2 parts Coir and 1 part of any of the next 4 ingrediants but you can use 3 of any of these.
This basic mix is 50% pumice and can be used for almost everything without further modification. As a plus, it is also easily cut or amended to accommodate special needs. Experimentation is encouraged. For example:

2 parts basic mix + 1 part pumice = 67% pumice - use this for the higher drainage requirements of many difficult cactus and more extreme succulents

2 parts basic mix + 2 parts pumice = 75% pumice - use as low organic content mix with super drainage for mesembs such as Lithops or Conophytums and very hard grown succulents such as Sarcocaulon or Othonna

1 part basic mix plus 1 part perlite = Very fast draining, low organic mix like above but retains even less moisture after watering. (Pumice is porous and will retain some water allowing slower drying of the mix then perlite.) Try this for Pachypodiums but be prepared to water frequently in the hot months.

1 part basic mix + 1 part organic material = 33% pumice - Good drainage plus higher organic content for plants like Aloes, Cucurbits (e.g. Momordica) and most tropical or sub-tropicals requiring constant moisture and more organic content.

The Spice Rack

Growing in pumice based or other soilless mediums requires more attention to the plant's requirements for food (fertilizer) and trace elements. I keep several things handy to spice up my basic pumice mixture. You may use any, or all, based on your understanding or observation of the plant's needs.

Osmacote 270 day formula - time release fertilizer that works well for fast growth in more organic mixes. Be sure to increase your watering in very hot weather to avoid excess salt buildup in the potting medium. Flood thoroughly,. wait 20-30 minutes and flood again to remove salts.

MicroMax Trace elements from the Osmacote people - a good and easy to use micronutrient mix compounded for nursery use.

Dolomite or Horticultural Lime - add this as needed to adjust the the ph of more acid (higher organic content) mixes.

Superphospate - good additive to promote root growth when potting bare root or potting on seedlings

Gypsum - the only way to add usable lime to mix. Good for cactus or succulents that grow naturally on limestone - just a pinch per pot

Marathon - an expensive but very effective granular systemic pesticide

Watering and Feeding

Now that we all have a few ideas for the planting mix, the next question is, "When do I water?" Like the potting mix question, there are many opinions.
If you take a survey for any given plant, you will get answers ranging from the reasonable to the absurd and some that are just plain impractical, like "Look up the weather for the plant's home area every day and water when it rains there." Although offered in good faith, such advice doesn't make sense because your plant is here, growing in your mix and weather, NOT there!! Watering by the calendar (i.e. don't water at all between October and April) is another suggestion that doesn't allow for the year-to-year or even month-to-month variations of growth and weather. Like during el NiÑo years!!

Watch and study your plants. If they are in active growth, they need food and water. Sometimes much more then you would think. This can be as often as every day or two during very hot dry weather with actively growing plants. When growth is over and dormancy begins, water and food needs drop drastically, or even cease.

Periodically check the soil moisture. Use a water meter, bamboo skewer or just lift the pot to see how light it has gotten. When the mix is almost dry, it's time to water. Remember, that even when fully dormant, most plants will benefit from a small amount of moisture in the mix to keep fine root hairs from dying. One of the major benefits of the pumice-based mixes is that it is hard to over-water due to the fast drainage plus the porous nature of the material which still slows complete drying.

Feeding, as mentioned above, is more important with soilless mixes. For most plants and growers, the easiest method is to feed at a reduced rate every time you water. If you adopt this schedule of feeding with every watering, just apply 1/8th to 1/4 th the fertilizer trength recommended by the manufacturer.

For plant food, I have used all the following with equal results. I suggest changing from time to time just in case there are trace element differences that could be good, or bad.

Grow More - 15-15-15 (From OC Farm Supply in 5# bags - very economical)
Miracaid Tomato Food -- 18-18-21
Schultz liquid -- 10-15-10
Peters Professional -- 10-30-20
Cactlizer - trace element additive from CSSA seed bank 1 - 2 drops per gallon

Most important of all -- feel free to change or experiment with any of this. The best mix and culture is the one that works for you and your plants.

Good Growing, Gene Schroeder

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