Crassula ‘Campfire’ with blue and green companion plants

What a wonderful moral education is provided in the growing of container plants.
Virtually unique among human activities, container gardening allows little escape from complete personal responsibility. When each leaf is green and every flower a sensual delight, you happily and justifiably take credit for that potted plant’s health and beauty. Only through the constant care and devotion of a single person – you – has such botanical perfection been achieved.
By the same token, should the plant not look so good or, heaven forbid, even die, there is no one to blame but yourself.
If growing plants in the backyard gives you some sense of psychic liberation, since – regardless of your station in life – you are at least in charge of what happens there, growing plants in containers may provide an inordinate boost to your mental health, because you alone will determine the fate of your chosen potted specimens.
Container gardening offers an absolute refuge and a final challenge to those in the middle-age and beyond. Having been disillusioned in marriage or in child-rearing, having failed to reach career goals or amass a fortune, a container gardener can point with pride, to a potted rose, hibiscus or begonia that has flowered on cue for several years. Here is tangible proof of expectations met or even surpassed, undeniable evidence of a job well done.
The best-tended gardens may succumb to the ravages of hail, such as we experienced last month, or to a late frost. Potted plants, on the other hand, are nearly always protected from the elements and, even when they aren’t, may be personally saved by you – by putting them under an overhang, shadecloth or clear plastic – at the first rumor of a storm.
Frequently, gardeners ask me if they can grow their favorite plants in containers. The answer is nearly always yes, since even redwood trees can be cultivated for 100 years in bonsai dishes. Besides, any plant’s seeds can be germinated in a container, and bulbs, divisions or cuttings from many plants can be turned into full-fledged container specimens as well. And, of course, any plant acquired in a container, can be kept that way for years. As the plant grows, it is simply a matter of moving it into increasingly larger containers, or alternatively, pruning its roots.
Once a plant is growing in a 15-gallon container, it may not be practical to move it to a larger pot. In such a case, the plant should be removed from its container and examined every year or so to check on root development. Any roots that start to circle the interior of the pot should be cut back. Where roots become exceedingly dense, as indicated by defoliation in older potted ficus trees, root ball volume should be reduced by one-third and new soil added to fill the empty space.
The soil used for growing large container plants need not be fancy. I was surprised to learn that many commercial growers of outdoor ornamental and shade trees use a potting mix that consists entirely of sawdust and top soil (the kind sold in nurseries). Best Turf Supreme – a popular lawn fertilizer – is sprinkled two or three times a year over the top and that’s it. As a rule, Los Angeles backyard soil is not recommended for container plants because of its poor drainage.
Outdoors, the easiest container plants to grow in full to filtered sun are the slow-growing Mediterranean fan palm (Chamaerops humilis) and the even slower growing Sago palm (Cycas revoluta), sometimes known as the Rolls-Royce of potted plants because it costs approximately $22 per inch of trunk. The pygmy date palm (Phoenix roebelenii) is also a favorite for half-sunny patios.  Combinations of succulents make reliable and low maintenance container gardens, too.
Moving from filtered sun into the shade, the feathery bamboo palms (Chamaedorea Seifrizii) perform well in containers, as do the lady palms (Rhapis excelsa). Nearly all agaves and succulents will live rather carefree lives in containers. Aloes create interest in shadier spots.
Container plants that are called upon for a steady display of color need a constant supply of fertilizer, especially those growing in full sun, where watering is frequent. A weekly dose of any complete water soluble fertilizer is suitable for evergreen flowering plants – such as bougainvillea or hibiscus – during the growing season. For annual flowers, application of a high-phosphorus product, every other week, is appropriate.