The Island Garden
Have you looked at your house plants lately? If not, this is the time of year to take a look. You want to inspect the root system, take a look at the growth, and maybe start them growing with a little weak fertilizer. While you are at it, check to the top of the plant for aphids and mealy bugs. If you see any signs of either pest, you will need to spray the plant. I find the best spray for aphids is Safer's insecticidal soap. If we get a mild day, do the spraying outside so that you won't have the smell wafting through the house. If you find mealy bugs, you can kill them with rubbing alcohol. Use a Q-tip to dap a little on each bug, then take the plant outside and spray it with a dormant or agricultural oil to suffocate any eggs. In spite of your best attentions, new eggs will hatch later and you should repeat the swabbing/ spraying routine about every two to three weeks until the plant is free of bugs.
To repot, if we get a mild day, take your plants outside and knock each plant out of its pot. If you can't take it outside, put some newspapers down, hold your hand over the plant stem to keep the dirt in place, and knock it out of its pot. Take a look at its roots. If the plant roots are growing around the bottom of the pot and have formed a dense mat of roots with very little potting soil, it is time to repot them into a larger pot.
First, tease the root ball out until the roots are untangled from their mat. You may break some roots while you are doing this or you may have to cut through the root ball to get the roots to unwind. That's OK, a little root pruning doesn't hurt the plant too much. If you have plants that can be divided, now might be a good time to do that. Ferns, for example, can be cut into two or four parts and replanted in separate pots. They will grow into new large plants. Another plant that often needs to be divided is clivias. If your pot has more than two plants in it, you might want to think about separating them into pots with just one plant. Don't worry, in a year or three you'll have several plants in each pot.
If you have bushy plants, you might want to cut them back a little. NO Rather than just shear the plant try cutting one or two branches out from within the plant to thin it and allow more light into the center. This will help to make the center grow a little more thickly. Another thing you might want to do with a bushy plant is to rotate it in front of the window. About every six months or so turn it 90 degrees so that each side of the plant gets an opportunity to grow toward the light. You'll find that your plant grows in a better shape if you turn it occasionally.
When repotting use a good quality potting soil. After you have repotted, tamp the soil down well and water the plant to help get its roots growing again.
When watering, keep in mind the old adage, "it's not lack of water that kills house plants it's overwatering." Don't water your plants too often. The most common cause of plant death is overwatering. During winter you need only water when the soil is dry. Stick a finger in it and test to see how dry it is. If no dirt sticks to your finger or your finger stays dry it's time to water. If potting soil sticks to your finger or your finger is moist do not water. It's that simple. In spring, as daylight hours grow longer, add a small amount of fertilizer to the water each time you water. Less than half a teaspoon is fine to start with, increasing to a teaspoon during the height of summer. You'll find that you need to water less during winter and a little more during summer, but rarely will you need to water more than once a week.