Have you ever had a pet frog, a bird, a hamster, or a goldfish? If so, you have some idea of what caring for a potted plant is all about. Constant vigilance, really. You want to feed it, but not too much. You need to make sure it is well-hydrated. You must look at it with a critical eye for any possible sign of stress or sickness at least once a day since any hint of a problem should be immediately addressed.
Not everyone who wants to grow plants has a garden. For such land deprived plant lovers, growing in containers is a necessity. Moreover, there may be a certain plant that you are just crazy about and simply have to grow and cannot contain yourself, so to speak, from growing in a pot.
Such seems to be the plight of Ingrid Vold, a recent arrival here, as expressed in the following email: “I got a great deal on two jacaranda trees that are five feet tall. I’ll probably live in an apartment for two or three years before planting them in the ground. I’ve been told here in Los Angeles they must be watered every day in the summer if they are in containers. I plan to keep their growth under control by pruning, keeping them six to eight feet tall. Does this make sense to you and are potted jacaranda trees less apt to bloom than those in the ground?”
You can containerize any plant and, under optimum conditions, it will bloom. The issue here is size. A jacaranda grows to a height of 50 feet and you will have to continually repot it in order to keep it healthy. There is an alternative, however, and that would be to grow it as a bonsai specimen.
Still, your plan is eminently feasible. You only want to make sure that your trees get maximum light until you move out and plant them in the ground. A sun-splashed balcony would be a preferred location or, better yet, the roof of your building, as long as your building is not so tall that it is exposed to strong winds. You could probably put some sort of panels or partitions around your trees to protect them from the wind should you choose the rooftop option. When containerized rooftop trees do not grow well, it is nearly always due to the wind factor, although intense reflected heat from the surrounding roofing material can also be a problem.
At a height of five feet, your jacarandas, more than likely, are in five gallon containers. If given lots of sun, they should not need to be watered more than once every few days in hot weather. To lengthen watering intervals, you can put the containers in deep dishes that hold several inches of water or place the five gallon containers in slightly larger pots with the gap in between filled with wet peat moss. This peat moss will insulate the soil in the five gallon containers, keeping it a bit cooler and less prone to drying out than otherwise, which could make a difference if you go away for a long weekend and there is a sudden heat wave.
If you want to keep your trees in their current containers for two or three years, you should take them out of their containers every few months to inspect their roots. If the roots start to circle the container, they will need to be trimmed because circling roots stunt the growth of container plants. You can keep a plant in a container for a hundred years or more (check out bonsai specimens), including redwood trees, as long as you regularly prune the roots. Also, if you keep tree shoots and branches pruned back as you plan to do, you will minimize root growth for the next two years until you can plant the trees in the ground.
A common mistake when it comes to container growing is to leave original soil in the container after it should be replaced. If your soil dries out quickly, it water goes down the sides of the root ball when you water, or if two years have elapsed since the last soil change, you should generally change your soil, especially when it comes to flowering plants. That being said, I know there are slow growing palms and succulents that might remain in the same container for years and years without needing to have their soil changed.
Are there any plants that you have grown in containers and of which you are especially proud? If so, please let us know about them.
Tip of the Week: The easiest container plants to grow on a patio or balcony in full to filtered sun are the slow-growing Mediterranean fan palm (Chamaerops humilis) and the even slower growing Sago palm (Cycas revoluta). The pygmy date palm (Phoenix roebelenii) is also a favorite for half-sunny patios. Combinations of colorful succulents, as well as the many aloe and agave species make reliable and low maintenance container gardens, too.
Moving from filtered sun into the shade, feathery bamboo palms (Chamaedorea Seifrizii) perform well in containers, as do lady palms (Rhapis excelsa).