Q I love plants and gardening, but I have the “blackest” thumb there ever was! I cannot even keep my Christmas poinsettia alive. I have tried numerous tips to monitor watering, sun, dryness, and so much more. I have tried the self- watering bulbs and fertilizer sticks. I live in South Dakota and want to grow indoor plants and a few herbs. Can you give me some new tips and ideas? I do not want to resort to fake plants!
A Poinsettias can be a challenge to grow well, particularly if they had a foil pot cover on them or were in a plastic-lined basket when you purchased them. The number one reason poinsettias die, as well as a lot of other houseplants, is that the potting media is kept too wet. If the potting media is too wet, there is very little oxygen available to the roots. Roots need oxygen to survive because root cells need oxygen to respire, just like all the rest of the living cells of a plant, or animal for that matter. Here is where the foil pot cover causes the problem because it makes hard to know how much water to apply and when. The first thing you should do when you get any kind of plant with a foil wrapper is to either remove it or at least cut some holes in the bottom so that excess water can drain out. That means that you will either need to place the plant in a sink when you water it or in a pot saucer to catch the extra water. Then empty the extra water out of the saucer so the plant never sits in water. So, the key is, water thoroughly, so water comes out of the drainage holes in the bottom of the pot, let the excess drain out, then do not water again until the potting media feels dry when you stick your finger down into it. Or you can lift the pot to see if it feels lightweight, or if the media has a lighter brown color, which can also be good indicators that the plant needs to be watered again. Then repeat the process of saturating the potting media in the sink, let it drain, then put the plant back in its growing location. Some people wait until the plant is wilted before they water. While this can be OK for some plants that can tolerate that much water stress, some plants will die in the process. Also, root rot, caused from too much water, can also cause a plant to wilt. Adding extra water to a plant that already has root rot is the last thing you want to do. Overwatering can also lead to other problems like infestations of fungus gnats and shoreflies whose larvae thrive in saturated growing media.
These sub-tropical plants like typical room temperatures but be careful to keep them away from hot drafts, cold drafts or next to cold windows. They can take quite a bit of sun exposure this time of year when the sun angle is fairly low in the sky. A west even a south-facing window is fine for now. When it gets sunnier in the spring, an east-facing window would probably be better. Also, if you have not already, use a pruning shears or sharp knife to cut off the colored bracts at the top of the plant. These modified leaves do not really help the plant to grow much, you want to encourage new shoots to develop with nice green leaves. A little half-strength soluble plant fertilizer about once a month should be all the plant needs.
BUT, while a lot of people get excited about successfully keeping their poinsettia alive for months after Christmas is over, they can be very difficult to get to come into bloom again for Christmas next year. They rely on the length of the night period to initiate flower buds and develop the colored bracts. If your plant is situated somewhere where it is exposed to artificial lights in your home after dark, this will throw off your plant’s timing and the plant will just stay green. You almost have to put a cardboard box over the plant every night at 5 pm and remove it again the next morning at about 8 am, starting about the first week in September until it blooms to enjoy this colorful plant again next year. Either just keep it as a green plant or better yet, add it to your compost pile and select a different kind of houseplant to enjoy instead. Most houseplants can be treated the same way that I described in the first few paragraphs of this article and will do fine.
Here are a few plants to consider growing while you green up that thumb of yours. The snakeplant (Sanseveria) which comes in several species, varying in size and color and is probably one of the easiest plants to grow. It can tolerate low light to full sun and can literally go for weeks without needing water but will grow better and faster if you follow the watering process described above. Another great plant to try are the Chinese evergreens (Aglaonema). This is another low-light tolerant plant, but it will perform better if it gets bright light. These usually come in a 6 to 8” pot, have leaves with light and dark green variegation with some cultivars even having reddish foliage. Dwarf rubber trees (Ficus) come in a wide array of sizes but are generally larger than the other plants mentioned here. They too are quite tolerant of varying light and watering. Another plant you may want to consider is the jade plant (Crassula) or other plants in this genus. These beloved plants have thick fleshy stems and leaves and are actually considered to be succulents. This means that they have a thicker cuticle on the leaves and stems that helps to prevent them from drying out too quickly. So, they do not need to be watered very often but watering should be increased when they are in active growth during the spring to fall. Like many other succulents and cacti, these plants need to be in a sunnier location to grow well.