Tropical plants lend gentle touches to your indoor environment. They’re like a piece of furniture that compliments your interior design and brings out the warmth of an area.
Most tropical plants do fine indoors and will even take some abuse. If properly maintained, they’ll live to a ripe old age, bringing you much enjoyment.
Here, we’re discussing their general care and maintenance. With patience and dedication, even a beginning gardener can develop a green thumb quickly.
Light & Temperature
Light is essential for photosynthesis. Photosynthesis is the process of food production in the plant. Carbon dioxide (CO2) from the air and water from the soil combine into an organic chemical compound called glucose or simple sugar.
The natural habitat for most tropical plants is a tropical rainforest where available light filters through the canopy of large trees. Therefore, most tropical plants need little direct sunlight.
Most tropical plants require sun filtered by 50% to 80%. For example, if direct sunlight comes in a window, a sheer curtain will provide the necessary light filter for tropical plants located near that window. Where plant directions specify high, medium, or low requirements, this means the length required of 50% filtered light.
Some plants, such as cactus, adapt well to growing inside with proper light. With these plants, try to create as closely as possible their natural conditions outdoors.
Using Grow Lights
Grow lights can supplement natural light requirements. Lights should be placed at the manufacturer’s recommended distance from the plant. Grow lights should be replaced every 12 to 18 months.
Introduce your tropical plants to changes in light and temperature gradually. 72°F is ideal for most tropical plants. Plants can survive temperatures of 50° to 100°F, but drastic or sudden light and temperature changes will send the plant into shock. An example of a “too drastic” change would be going from 4 hours to 8 hours of light or a sudden 15° to 25° change in temperature.
When relocating a plant, seek a similar environment and make changes gradually over three weeks. Never place an inside plant in the direct flow of an air conditioning or heating duct. It’s best to make the changes early in spring so that, as natural changes occur, light and heat intensify naturally as the season progresses.
Many homes and apartments have central air and heat. These units usually keep the humidity at about 30%. Most tropical plants do best with humidity of 80% to 100%, as in the rainforest. You can add humidity by:
- Spraying foliage daily with a mister.
- Placing the plant on a tray or saucer containing one inch of gravel with water. This allows the water to sit below the pot and evaporate.
Plants shouldn’t sit directly in water. Placing charcoal in the tray will help keep things smelling fresh. Clean the tray once a month to discourage fungus or disease.
Soil & Fertilizers
Use commercially prepared potting soils to repot plants or to replace missing soil. Premium soil mix is ideal for most houseplants growing outdoors in containers.
Fertilize every 3 to 4 weeks in the summer growing season with a water-soluble house plant food, such as 20-20-20 or fish emulsion. In the winter months, every 2 months is sufficient. Follow the manufacturer’s dilution rates.
Leaching & Watering
Leaching is a process for washing away accumulated fertilizer salts. Where excessive salt build-up exists, you’ll see a white substance on the pot or surface of the soil mixture. Run water through the soil thoroughly to dissolve the salts and let them drain away. Wait 15 to 20 minutes and flood once more to remove the salts.
Watering plants is an art. Novices to plant care often believe a good soaking is a cure-all for all plant ailments.
But one way to test soil moisture is to stick a finger 1 1/2 inches to 2 inches deep. If the soil feels dry, the plant is thirsty and should be watered until the soil is evenly moist, not saturated. If in doubt, let the plant dry out instead of watering more. Wilting is less harmful than rotting caused by overwatering.
Rain or distilled water is excellent for watering indoor plants, though not compulsory. Also, when using tap water, let it stand, if possible, for 24 hours to attain room temperature and release harmful gasses.
A container can be plastic, metal, clay, or ceramic. There’s no unique benefit to using one particular pot type versus another, except that you should avoid aluminum and copper. Roots grow away from aluminum and copper and will grow out of the pot.
Plants will grow well in all other container types. Each container type has slightly different requirements to consider. Some tend to allow the soil to dry out faster than others. Therefore, you have to monitor watering closely. Conversely, others hold water longer, and you should be careful not to overwater.
All containers, without exception, should have a drainage hole in the bottom.
Plants should be repotted when they become root bound. Root-bound conditions exist when you see roots coming from drainage holes or when, upon removing the plant from the pot, you observe solid roots with very little soil.
Plants should be repotted in a larger container not exceeding 2 inches in diameter more than the original container.
CAUTION: When potting, firm all soil, leaving no air pockets.
The most common pests affecting tropical foliage plants are spider mites, mealybugs, aphids, and scale insects. Should you suspect insect problems, bring a sample into your Anawalt Garden Center for proper identification, or use an app like PlantSnap.
Again, use a plant app, or take a leaf, a branch, or an entire plant to a trained expert to examine and more accurately diagnose a suspected ailment. Some signs of plant diseases are:
- Abnormally growing roots, stems, and other parts of the plant
- Yellowing leaves, unusual leaf spots, loss of leaves
- Drooping plants, even after watering