This article describes general tips on how to care for your houseplants.

Lighting

Light is probably the most essential factor for house plant growth. The growth of plants and the length of time they remain active depend on the amount of light they receive. Light is necessary for all plants because they use this energy source to photosynthesize. Light strength influences the production of plant food, stem length, leaf color, and flowering. The intensity of light a plant receives indoors depends upon the nearness of the light source to the plant. The amount of light need is usually measured in foot-candles (ft-c). Plants can usually be put into one of three lighting categories: low, medium, and high light.

Low Light
Low light plants prefer around 75-100 ft-c. This type of light can be found by a north facing window, a corner, or in an artificially lit room like an office. Because the amount of light is low the water in the plant does not dry up as quickly as it would with a high light so it is typically suggested you only water these plants every 7-10 days. Common plants that need low light are Philodendrons and Dracaenas.

Medium Light
Medium light plants prefer around 200-500 ft-c which is typically found by an east facing window, in the middle of a room with natural light, or by a window with diffused light. Plants that require medium light usually need to be watered every 5-7 days. Common plants that prefer medium light are Arrowhead Ivy, Dieffenbachia and some plants with variegation (two tone leaves).

High Light
High light pants prefer around 500-1000 ft-c. This type of light can be found by windows with southern exposure but you want to make sure these windows have some sort of diffuser like mini blinds or a sheer curtain especially during the summer months. Because of the high amount of light concentrated on these plants they should be watered every 2-4 days. Many blooming and tropical plants require high lights.

Watering

Once you have made sure your indoor plant has the right amount of light the next most important factor in keeping your plant healthy is watering. Many house plants suffer from either too little or too much watering. People want to stick to a watering schedule but this doesn’t always work. Several factors influence the frequency of watering, including the type of plant, temperature, humidity, light, pot size, plant size, potting mix and drainage. In order to tell if your plant needs to be watered you must test the soil. Common and easy ways to test the soil include:

• Feel the soil – The most accurate measure of when to water your plant is when the potting mixture feels dry to the touch. Put your finger about 2 inches in the mix; if the soil feels dry then it needs to be watered.
• Tap on the pot – When the potting mix in a clay pot begins to dry, it contracts away from the sides of the pot. Hit the side of the pot, if the sound is muted, the soil is damp; if the sound is hollow, the plant needs to be watered.
• Estimate weight – As potting mixtures become dry, and a distinct loss in weight is seen. When the pot feels too light its time to water.
• Look at soil color – Potting mixtures will change from a dark to lighter color as they dry. When the soil starts looking light its time for watering.

When watering is required make sure to completely saturate the soil by evenly pouring the water around the edges, not directly on top of the plant. Once the water is coming out of the bottom of the pot make sure to empty the excess water out of the tray. Drainage is crucial for the survival of your plant, leaving the water in the tray or at the bottom of the pot keeps the roots from taking in oxygen and this will cause root rot.

Other things to keep in mind when figuring out how often to water your plants include the type of pot it is in; unglazed clay pots are porous and will absorb some of the water so plants in clay pots should be watered more often then plants in plastic or glazed pots. Also, do not use cold or hot water; only use water that is room temperature.

Common Plant Problems

Houseplant problems can often be avoided by knowing your plant and what type of environment it needs to be placed in. Unfortunately conditions change and even in the right environment your plant can suffer from leaf discoloration or other sickly symptoms. The problem with diagnosing some of these symptoms is that some symptoms may be a sign of opposite causes like over or under watering. In order to find the right solution to your plants problem you have to examine your home’s environment and your plant care practices. After you have looked at the environment you can refine your diagnosis to the most likely causes. You must also remember that these symptoms can be caused by a combination of problems. Here are a few common symptoms and the possible reasons for them.

Browning Leaves

• Over or under watering
• Conditions that are too hot and dry
• Too much sun exposure
• Too much fertilizer

Yellowing Leaves

• Too much or too little light exposure
• Not enough or too much fertilizer
• Poor drainage (root rot)
• Mineral (iron or nitrogen) deficiency. If new leaves are yellow, iron is needed. If older leaves, it's most likely nitrogen

Black Leaves

• Over watering
• Room temperature is too cold
• Fungal infection

Curling Leaves

• Over watering
• Room temperature is too cold
• Not enough humidity

Wilting

• If the soil is dry- needs to be watered more
• If the soil is damp- needs to be watered less
• Room temperature is too warm
• Root rotting cause by lack of oxygen

Spots on Leaves

• Dry brown spots indicate under watering
• Soft brown spots indicate over watering
• White or yellow spots indicate that the water is too cold
• Too much sun exposure

Leaves Falling Off

• Occasional leaf drop is common in many plants, especially new ones
• Mature plants will generally drop older leaves, usually at the bottom
• A sudden drop of most or all leaves is a symptom of sudden shock like extreme temperature change
• Leaves falling from the bottom means too little light
• Leaves falling from multiple areas means the plant is under watered

Buds Fall Off

• Insufficient watering or humidity
• Insufficient lighting
• Change in temperature

With over fifty years of experience in plant care and floral decorations, Visser’s Florist in Anaheim, CA wrote this article using knowledge that is only gained by experience. If you have any questions don’t hesitate to call.