GROWING CACTI AND SUCCULENTS
General information

Cacti are part of a larger group of plants called succulents. Through natural selection most Cacti species lost their leaves, which allowed too much evaporation in the desert. Their stems became thick, and round to minimize surface area, and to store water. To protect themselves from the Sun and predators many species developed spines and hair, waxy skin, along with bitter alkaloids.

Most Cacti do fairly well as house plants; however they are quite slow growing. Be sure and save the sunniest spots in your house for your Cactus plants as they need lots of light. Don't forget to turn them every few weeks so that they are evenly illuminated. If you are going to grow some of your Cacti to flower, or for seeds, then don't move them while in bloom. They are very sensitive to disturbances at this stage and can drop the buds.

Strange as it sounds, you can sunburn even a Cactus. If you are going to put your Cactus outside, they must first be acclimatized. Keep them in the shade for a few weeks, and then move them into partial sun. Don't be in a hurry to scorch them under a hot July Sun, give them a month or more to get gradually used to it. If after you put it outside your cactus starts to acquire a lighter green or tan tint, it is probably sunburned; move it to some shade.

Don't over-water your Cacti. However, when you do water, soak it good - like it just went through a thunderstorm. Cacti and other succulents prefer hot and dry conditions and a soil that affords good drainage and aeration. Let the soil dry out completely between waterings during the growing season, and water even less during the winter. When watering your Cactus don't forget to use lukewarm water, cold water can shock the roots. A good way to test if your cactus needs water is to poke a small, clean redwood stake in the soil. If it comes up with small particles clinging to it, then the soil is still moist.

Cacti prefer to be in unglazed clay pots with a layer of course gravel in the bottom. Most Cacti have far ranging lateral roots so a shallow, wide clay pot is preferred. Be sure not to put your cactus in too large a pot because that can lead to later problems-primarily root rot. A tall narrow pot often leads to stress and stunted growth.

Avoid transplanting too many times as this can also shock the plant. The best time to transplant is during the spring. Have a plastic fork on hand to help poke soil into those tight places. Clean off any loose soil that might be stuck to your plant with a small brush. Don't water for a few days.
A tip to remember. When handling small Cacti, use a pair of tongs, and for larger ones, use a rolled up newspaper. Cactus spines can be very sharp and can penetrate gloves, as you may well become aware of. Ouch!

A good soil mix is essential if you expect good growth and health for your Cactus. They prefer a porous alkaline soil. Contrary to popular belief, Cacti don't grow well in plain sand. There are several good brands of commercially available Cactus soils that come prepackaged. For those of you who want to do it yourself, the easiest formula is to just mix equal parts of commercial potting soil and builders sand. You can also add some bone meal and ground limestone - but not necessary.

All mature actively growing cacti need to be fed regularly during the growing season. Formulas are available that are specifically designed for cactus like 7-40-6. (Nitrogen, phosphorus, potash) Use a mixture with a low ratio of nitrogen, as cacti can be burned by it. A commercial formula such as miracle grow or rapid grow can be used, but should be diluted to half strength. Regular Bone Meal, available at most Garden Centers, makes an excellent organic fertilizer. Don't forget the macro-nutrients like Iron (Fe), Calcium (Ca), Sulfur (S), and Magnesium (Mg). Also important are the micro-nutrients Copper (Cu), Zinc (Zn), and Manganese (Mn).Many Cacti have beautiful and fragrant flowers, but they can be quite hard to get to bloom. The optimal conditions to induce flowering are, a cooler temperature (especially at night), reduced day length (12 hours or less), and variations in nutrients (lower nitrogen levels)..

When you order your plants, don't be concerned. Cacti are well suited to being packaged for extended periods without light or water. They will almost always arrive at your house in good condition. As most species are cold resistant, they can be shipped any time of year - except the dead of winter. Since Cacti are tough and hardy, they don't have to be shipped by an overnight service, like most tropicals.

GROWING CACTI FROM SEED

Cacti should be germinated in sandy, well-drained soil. A commercial sterilized cactus mix works fine. Use small ceramic pots 5 x 5 cm (2 x 2 inch) since they allow soil to dry out completely (after germination) and prevent root rot. Most cacti germination temperature should be around 70 degrees F. Peyote should be around 80 - 90 degrees.

Place a small piece of cotton over the pots drainage hole and pull a few strands thru to act as a wick. Fill the pot with cactus mix. Place the seed on top of the soil in the center of the pot. Additional soil should be sifted through a tea strainer to barely cover the seed.

Put the pots in a container with a translucent snap-top lid."Bottom" water the pots by pouring about 1/4 inch of tepid water (never cold) into the container. Bottom watering causes the roots to grow strong, from searching for the water. When you first plant the seeds, you should also top water once with a fine mist water sprayer. The soil should be well watered throughout but not soggy. Place the lid on the container and place it outside (April - July) or under artificial lights (For an earlier start indoors).

The tupperware creates a mini greenhouse, and should be kept closed except for a daily check on the seeds progress (which allows some necessary air circulation) until the seeds germinate. They don't need any additional watering or misting during this time (unless for some reason the water level in the container drops below 1/16 inch). Be careful that your mini greenhouse isn't too humid. Wipe off any beads of condensation that form on the containers lid. Also be careful that the temperature isn't too hot, as this can cook the seedlings.

Many species germinate within a few weeks. When the seedlings first appear, they look like tiny green spheres. After they have sprouted, replace the container lid with a piece of stretched muslin secured with string or a rubber band. This will allow air circulation, which can be increased by placing a fan above the container. Adequate air circulation is essential as all green plants require plenty of CO2 to grow. Seedlings are more sensitive to light than mature plants. They should be dark green. If they are a reddish or brown color, they are receiving too much light, and additional pieces of muslin must be placed over the top of the container to shade them. If they are yellowish then they are not getting enough light.

When the seedlings have germinated, place a thin layer of very fine aquarium gravel on the surface of the soil. This gravel will help to support the new seedlings and protect the surface from drying out too quickly. Be careful to gently scoop out any green moss-like growth that might appear because of high humidity.

After four to five months (when spines have formed on seedlings) remove the muslin shading for one or two hours a day to give the seedlings more light. Stop bottom watering and use a watering can twice a week. Water around the seedlings, not on top of them. The seedlings should be misted occasionally (not a lot) in hot weather. Seedlings should be brought inside for their first winter, and kept moist (they cant handle very cold weather). They should be placed in a sunny window away from cold drafts.

Also note: The use of some sort of fungicide when germinating cacti seeds is almost mandatory due to the high humidity levels involved. I have heard reports that the fungicides Daconil and Consan 20 can cause reduced germination rates, and are not recommended. I have heard a recommendation for the brand name Chinosal, but have not used it personally.

GROWING CACTUS INDOORS, UNDER LIGHTS

It is recommended that a minimal level of illumination to grow Cactus indoors is around 15 watts per square foot (150 watts/ sq. meter). Fluorescent lighting should be placed 12 - 15 inches (28 - 35 cm) from the top of the plants. High Intensity Discharge Bulbs should be placed considerably further away (depending on wattage). Plants do much better if the day length is kept more or less constant, depending of course on the season. Be sure and use a timer set to 12 - 18 hours a day. Most plants grow best if the light, dark period matches that of their native habitats. When using artificial lights, be sure and use reflectors to catch and concentrate as much light as you can on the individual plants. For maximum growth, your plants should be rotated about every two weeks to assure even illumination.

Cactus, like most plants are more sensitive to certain frequencies (colors) of light. This is usually towards the blue and red parts of the spectrum. For best results use a grow light type of tube for fluorescent lights, or for killer results, step up to a metal halide. These kind of lights produce more light in the colors that the plant can use.

Metal Halide fixtures also produce a great deal of heat and some UV radiation, your Cactus will love it. These fixtures have proven to work well in an indoor environment as they have been used by "closet" growers successfully for years.

DISEASES AND PARASITES OF CACTUS

Usually Cacti are very disease free, but occasionally. Especially if the plant is over watered, any part may be susceptible to molds or rot. If the roots are infected, then most probably the core is also and the plant is lost. If an above ground part of your plant is affected, the area should be cut out with a sharp knife to remove any infected matter. The cut parts should then be dusted with sulfur or a fungicide.

If any of the roots are affected then the plant should be unpotted and thoroughly cleaned. Of course all rotted or dead parts are removed. The plant should then be repotted in pure sand and kept dry at a temperature between 64 - 70 degrees. Cactus are tough and are designed to withstand long periods of drought, they should start growing again when healed and watered.

The only pests that may plague your Cactus collection are scale insects belonging to the superfamily Coccoidea, and nematodes. Of interesting note, one species of scale is grown on opuntia Cactus so that their eggs can be harvested and made into a red dye.

An environmentally friendly method of controlling scale is to spray the plants with a mixture of rubbing alcohol and nicotine. If nematodes are present, the plant must be unpotted and the roots cut off. It is then repotted in a sterile mix till rerooted. The soil should then be sterilized and all infected matter burned.

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