By Michael PettayHorticulturist, University of Florida/IFAS Extension EducatorDish gardens can make a snazzy display for plants such as cactus and succulents.
What's the difference you say? Well, succulent is a generic term that refers to any plant that has thick, fleshy leaves, stems or roots adapted for storing water during dry periods. Cactus refers to a specific family of succulents, native to the Americas, characterized by thick, water storing stems and often by long, sharp spines. In short, all cacti are succulents but not all succulents can be called a cactus!
Succulents have leaves, stems or roots that store water from the rainy season for use in the dry season. Plants in the family Cactaceae, from the Greek 'kaktos', for thistle, are stem succulents.
Cacti usually have spines, which are actually modified leaves. While leaves are very good at photosynthesis, and cooling plants off, they lose water and generally can't take much heat. Cacti photosynthesize through their stems and tolerate heat very well.
Both types of plants need very little care, prefer low humidity, and come in many shapes, sizes and colors that can add interest to a table top, a window sill in a brightly lit room, or a sunny porch. I actually have cactus gardens in larger pots in full sun around a backyard deck.
Start with a relatively shallow pot, container or dish, at least two to three inches deep. Clay or terra cotta works better for plants that prefer to be on the dry side. Make sure it has drain holes in the bottom! Plastic pots will work if you are cautious with watering but be careful in full sun. The sun shining on a dark colored plastic pot can very quickly overheat the roots!
Fill it with special cactus potting mixture or make up your own using equal parts of potting soil and sand. Choose a few interesting looking plants and leave them enough room to grow a little. I usually tell folks to use an odd number of plants for a more interesting, natural looking pattern, and to leave room for a few larger stones and a thin top dressing of sand or gravel. Although they certainly look like they could take care of themselves, cacti are slower to react to poor care than other types of plants, so only purchase those that are healthy. Look out for scars, bruising, broken stems or spines, or stems that are long, thin and pale. Remember, also, that cactus may be sun types or shade types.
Sun type cactus look like what most folk would think of as a cactus; heavily armed, stem succulents. They can take direct sun outdoors and would prefer a South or West window if kept indoors.
Shade cactus are critters like Christmas cactus (Schlumbergera) that require special care and probably would not be good additions to a dish garden.
Be sure to have your gloves handy when working with cacti. Or you can also fold several sheets of newspaper and place them lightly around a cactus when you lift it out of its original pot for transplanting.
Allow your dish garden to dry out between waterings. Every two weeks during their active growth period would probably be adequate.
Cacti need fertilizer also, but not as much as other types of plants. Fertilize monthly, from April to October, with something in roughly a 5-10-5 ratio, such as tomato or African violet fertilizer, at one half the label recommended strength.
Place it in a sunny spot and enjoy!