Here are a few key factors you should consider when choosing the type of lamp, or combination of lamps, you will use to grow your plants: the spectrum of light provided; that is, the balance of cool and warm colors and how much of each is provided; the usable quantity of light the lamp provides; the amount of heat output from the lamp; and the amount of light, or the number of hours, you intend to light your plants given their daylength requirements and the lamp’s energy efficiency.

As a general rule, the less expensive the purchase price of the light setup, the more expensive and less effective it is to run. You will get much better results if you provide the right intensity of selective or full-spectrum light that is specific to plant growth.

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A few orchid species require short-day photoperiods in conjunction with cool temperatures to flower, such as some species of Cattleya, Dendrobium, and potentially some species of Phalaenopsis.

For these types, you’ll need to combine cooler temperatures and shorter daylengths from midfall through winter, then lengthen your lighting period again in spring.

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Not all plants will thrive indoors without supplemental light, but there are a few easy and tough houseplants that will tolerate low light conditions in your home. Snake plant (also known as Mother in law's tongue) or Sansevieria spp., are one of the best plant choices for low light. There are many varieties to choose from, ranging from large to compact.

There are significant differences in light intensity as you move away from windows and between the rooms in your home. A plant that thrives in the windowsill may struggle just a few feet away. So be sure to pay attention to how your plants is growing...or not growing...after you place it in a low light area. If it's struggling, move it closer to the window.

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Kelvin temperature is used to describe the visual color of light that a lamp emits. Technically, it is a measure of how white a piece of tungsten steel is when it’s heated to a specific temperature in degrees Kelvin. A lamp with a Kelvin measurement of more than 5000 Kelvin (K) produces more light in the cool blue spectrum.

Lamps with a lower measurement, in the 3000K or lower range, produce more light in the warm red spectrum. Kelvin temperature is not a measurement of actual hotness or coolness of the lamp, but rather the visual temperature of light, which can have a big impact on how your indoor space looks.

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In some cases, every place that a plant leaf is wounded is an opportunity for rooting. This begonia leaf below has been damaged, which caused it to develop tiny baby plantlets along the leaf vein.

Now, the leaf can be laid flat on the soil surface, and the little plantlets will begin to root.

Scale is a tough greenhouse pest,that is prone to attacking citrus. They are oval-shaped insects with either a hard or cottony shell, with different colors. They cluster on stems and base of leaves, and I have even seen them overwinter on pots.

To help control all pests and diseases, always keep your pots, seed trays, and tools clean. You can clean and sterilize reusable pots and trays with solutions of hydrogen peroxide, a 10 percent bleach solution, or diluted vinegar.

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Tomatoes are a warm-season crop that can grow at temperatures between 60°F and 80°F (15–26°C), but that doesn’t mean they will perform their finest at a constant temperature of 80°F (26°C). If you have tomato fruit on your plants but they just won’t ripen, temperatures are consistently either too cool or too hot.

Plants are adapted to cooler nights in their outdoor environment, so they will perform better with temperature changes that mimic their natural habitat.

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A good technique for most in-home growers is to start seedlings, cuttings, and young transplants using cool full-spectrum LED or cool full-spectrum high-output (HO T5) fluorescent lamps. If you’re growing fruiting crops, you can switch plants or lamps to a warmer spectrum (more red light) once you’ve bumped them up to larger pots to trigger stem elongation and flowering.

This grow tent has two separate lighting sections; one with cool-blue light for vegetative plants, the other with warmer red light for flowering.

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