Tropical House Plant Care


Tropical plants lend gentle touches to your indoor environment. They are almost like a piece of furniture that compliments your interior design and brings out the warmth of an area.

In general, most tropical plants do fine indoors and will even take some abuse. If properly maintained, they will live to a ripe old age, bringing you much enjoyment.

Below, we touch on the general care and maintenance of tropical plants. With patient application, even the beginning gardener can develop a green thumb in a very short length of time.

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 are combined into an organic chemical compound called glucose or simple sugar.

The natural habitat for most tropical plants is a tropical rain forest where available light is filtered through larger trees which form a canopy. 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.

There are some plants, such as cactus, that adapt well to inside growing with proper light. In the case of these plants, try to create as nearly as possible their natural conditions outdoors.

Using Grow Lights

Grow lights can supplement natural light requirements. Lights should be placed at the manufacturers recommended distance from plant. Grow lights should be replaced every 12 to 18 months.

Tropical plants should be introduced to changes in light and temperature gradually. The temperature for most tropical plants should be maintained at 72F. Plants can survive temperatures of 50 to 100F, but drastic or sudden changes in light and temperature will cause the plant to go into shock. An example of a too drastic change would be going from 4 hours of light 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 a period of 3 weeks. Never place an inside plant in the direct flow of an air conditioning or heating duct. Changes should be made early in spring so that, as natural changes occur, light and heat are intensified 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 found in the rain forest. Humidity can be added 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 should not sit directly in water. Charcoal in the bottom of the saucer or tray will help keep it smelling fresh. The saucer or tray should be cleaned out once month to discourage fungus or disease.

Soil & Fertilizers

Use commercially prepared potting soils, such as Ferti-lome Potting Soil, 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 manufacturers dilution rates.

Leaching & Watering

Leaching is a process for washing away built up fertilizer salts. Where excessive salt build-up exists, you will see a white substance on the pot or surface of the soil mixture. Run water through soil thoroughly to dissolve the salts and let them drain away. Wait 15 to 20 minutes and flood thoroughly once more so that the salts will be removed.

The watering of foliage plants should be considered an art. Newcomers to the care of foliage plants tend to consider a good soaking a cure-all for all plant ailments. But common sense should prevail. A good method to test for soil moisture is to stick a finger down into the soil 1 1/2 inches to 2 inches. If it feels dry, the plant is thirsty and should be watered until soil is evenly moist, not saturated. If in doubt, let the plant dry out more rather than water more. Wilting is less harmful than rotting caused by over watering.

Rain water or distilled water is excellent, though not compulsory, for watering indoor plants. Also, when using tap water, let it stand, if possible, in a container for 24 hours to attain room temperature and to release harmful gases.


A container may be plastic, metal, clay, or ceramic. There is no special advantage gained by the use of one particular type of pot over another, the exceptions being aluminum and copper. Roots grow away from aluminum and copper and will grow out of the pot. Plants will grow suitably in all other container types. Each type of container has slightly different requirements which should be considered. Some have a tendency to allow soil to dry out faster than others. Therefore, watering has to be monitored more closely. Conversely, others hold water longer and therefore one should be careful not to over water.

All containers should have a drainage hole in the bottom. There are no exceptions.

Plants should be repotted when they become root bound. Root bound conditions exist when you see excess 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, be sure that all soil is firmed, leaving no air pockets.

Insect Control

The most common pests affecting tropical foliage plants are spider mites, mealybugs, aphids, and scale insects. Should you suspect insect problems, bring a sample in to an Heirloom Gardens for proper identification.

Plant Diseases

Bring in a leaf, a branch, or an entire plant for a trained Heirloom Gardens 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; also yellowing leaves, unusual leaf spots, loss of leaves, and drooping plants, even after sufficient watering.

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