Reliable and Rewarding Houseplants
By Emma Erler
UNH Extension Education Center Coordinator
If you pay attention to trends, you have undoubtedly noticed that houseplants have had a resurgence in popularity. They are highlighted in home-decorating catalogues, cover the shelves of boutiques and coffee shops and have a large devoted section in many garden centers. They’ve even been featured in wedding bouquets.
Whether you’re simply interested in plants, just enjoy their aesthetics or want to take advantage of their ability to purify the air, a wide variety of indoor plants can be grown anyplace with a little light. That’s one way to deal with New Hampshire winters.
Success comes down to choosing the right plant and following a few simple care practices. While some houseplants are forgiving when it comes to watering transgressions or inadequate light, others are best left to professionals. Keep reading if you’ve ever struggled to keep a houseplant alive.
Almost all common plants grown indoors are native to tropical rainforests and desert regions. Without exception, plants are happiest when they are grown under similar conditions to what they prefer in the wild.
For example, succulent plants typically come from arid regions with full sun exposure. Thus, in northern places like New Hampshire, they will only thrive if they are grown in a well-drained potting mix in a bright window with southern exposure.
Though a cacti or succulents might look nice on the coffee table, they are unlikely to thrive long-term. If you have limited light in your home, you are better off trying a plant that can tolerate those conditions, such as one of the many rugged foliage plants that can be found at many garden centers.
Those with bright, sunny windows (south-facing) have the option to trying one of the many easy-to-grow succulents. A few of the most reliable options include: agave, euphorbia, haworthia, kalanchoe, rhipsalis, jade (Crassula) and aloe.
If foliage plants are your thing, Chinese evergreen (Aglaonema) or silver squill (Ledebouria socialis) are forgiving possibilities. Place these plants as close to a window as you can, and, if possible, move them outside to a sunny spot for the summer.
East- or west-facing windows are suitable for a suite of tough plants that enjoy moderate light, such as African violet (Saintpaulia), tuberous begonia, goldfish plant (Nematanthus), peperomia, Norfolk island pine (Araucaria heterphylla), hoya, ZZ plant (Zamioculcas zamiifolia), prayer plant (Maranta and Ctenanthe) and dracaena.
All of these plants will certainly take additional sun exposure, but they don’t absolutely need it. If they aren’t getting enough light, their leaves may turn darker and their stems may start to stretch.
Rooms with low light or north-facing windows can still accommodate a handful of reliable houseplants. Philodendron, ivy, pothos (Epipremnum) and certain ferns (Polypodium, Davallia and Asplenium) will grow in dim locations, albeit more slowly than they would with more light.
If you have a tendency to forget to water, try especially rugged plants such as cast iron plant (Aspidistra) and snake plant (Sansevieria). Though slow-growing, both of these are difficult to kill without wanton neglect.
Any new plant brought home can be a source of insects and diseases. Thoroughly check plants before purchase for any signs of stress, infection or infestation. Insects will often hide on the undersides of leaves or at the junctions where leaves connect with stems.
Gently pull plants out of their pots to see if their roots are white and not brown or mushy. Also look for yellowed leaves and rot near the soil line — indications that the plant may have been consistently over-watered.
Unusual spots or blotches on leaves might be evidence of a fungal infection and should be avoided. And, of course, skip plants that show signs of bruising, splitting or excessive breakage.
Watering is the next stumbling point for indoor gardeners. Proper watering starts with choosing the right container to grow your houseplant in.
The material a pot is made of matters much less than whether it has a bottom drainage hole. Pots without drainage allow excess water to pool around the roots, eventually causing root rot and death.
It is also important that the pot is the right size. A good container will provide enough room for the roots and space at the top to allow some water to pool when watering. Pots that are too big will keep plant roots wet for too long and cause issues.
Equally essential is using a high-quality soilless potting mix made of peat moss, perlite, vermiculite and lime. Specialty mixes are sold for orchids, cacti and African violets, and while not absolutely necessary, can provide benefits to those plants.
Overwatering and underwatering are responsible for most plant deaths. Watering should never be done on a schedule — only when plants need it. Most plant roots are usually located in the bottom two-thirds of a pot, so do not water until all the soil is nearly dry. An easy way to check is by sticking your finger into the soil and feeling for moisture an inch or so down.
The weight of the pot can also be an indicator; light pots need watering, heavy ones do not. Apply water until it drains out of the bottom of the pot. Empty any water that has collected in saucers after five to 10 minutes to prevent root rot.
Fertilizing houseplants is a task that is often overlooked. Although many popular houseplants are relatively slow-growing and have fairly low nutrient requirements, they still need a fertilizer boost periodically for healthy growth.
Most soilless potting mixes contain few, if any, plant nutrients, and those that do contain added fertilizer that will eventually be exhausted. If you notice that your plants are starting to look pale, it’s probably time to fertilize.
Which fertilizer product is best for you depends mainly on what you are growing. Different fertilizers contain various percentages of the three essential macronutrients: nitrogen, phosphorus and potassium.
Suitable houseplant fertilizers will contain all three macronutrients, although different percentages will be better in some situations than others. In general, foliage plants grow best with fertilizers that are high in nitrogen, while flowering plants tend to prefer those that have more phosphorous.
There are many specialty houseplant fertilizers that work quite well for specific plants. However, a balanced fertilizer such as 10-10-10 (10 percent nitrogen, 10 percent phosphorus, 10 percent potassium) is usually suitable for a majority of common houseplants. Be sure to carefully read the label and apply only as directed, because over-application can quickly damage plants.
Growing houseplants can be enjoyable and rewarding. It might take some experimenting to figure out what you can grow most successfully, but that is part of the fun.
By choosing a reliable houseplant with needs that match the indoor conditions of your home, watering only when needed and fertilizing judiciously, you may find that houseplants make an attractive and permanent addition to your home.