The world of LED technology for growing plants has exploded over the past few years. Their growing popularity is based on improving cost and energy efficiency. Most of the self- contained growing units on the market, such as those intended for growing greens or herbs on your kitchen counter or even integrated into your kitchen fixtures, use LEDs.

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When you're growing tomatoes in containers, it's important to remember that their root systems typically grow wider than deeper. Tomatoes growing indoors will need a good sized container and typically need to be staked. I've been asked about growing tomatoes in fabric containers, which I love for many reasons. Fabric containers do allow plant roots to breath and can help prevent over-watering and root girdling. They are also washable and reusable.

BUT, sometimes fabric growing pots can lose too much moisture too quickly for tomato plants, especially in a warm environment. So I don't recommend growing tomatoes outside in fabric pots if you live in a hot climate. If you're growing tomatoes indoors in fabric pots, under HID grow lights, know that you'll probably have to water them more frequently.

New BOOK! Gardening Under Lights: The Complete Guide for Indoor Growers

Many LED grow-light fixtures labeled as full-spectrum may provide a mixture of only red and blue light, sometimes with IR and UV mixed in. Technically they are not full-spectrum, but nanometer-specific. The visible light these lamps produce has the appearance of a distinct color—blue, red, pink, or purple.

This is not a problem for your plants, as they use these spectrums most effectively, but if you don’t want distinctly colored light in your living room, these color-specific LED fixtures are better suited for the closet or grow tent.

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Microgreens can be grown year-round in side your house. They do not take up much room and grow quickly. You need only about 2 square feet of space to grow a full tray of microgreens. Microgreens need bright light as they germinate. Grow with LED or HOT5 fluorescent grow lamps.

Shallow trays and bowls make good containers for growing microgreens. Harvest after the seedlings have developed only a few true leaves, which typically occurs in 9 to 14 days. Use sharp scissors or herb snips to cut the greens off just above where they are rooting. Use fresh as harvested microgreens don't keep long in the refrigerator.

New BOOK! Gardening Under Lights: The Complete Guide for Indoor Growers

Plants have varying requirements for how, where, and when to take cuttings, the ideal size of the cuttings, and how long they may take to root. Some plants, such as succulents, will root from the base of a leaf.

Others, such as begonias and African violets, will root straight from the leaf surface. This practice is called taking a split-leaf cutting.

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If you are considering using an HPS lamp exclusively in an enclosed space that does not receive any natural light, your plants may tend to elongate with thinner stems in a shade-avoidance response.

The bean plants on the right was grown from seed under only HPS lighting; note its very elongated internodes. The bean plants on the left was grown under a CMH lamp.

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White full-spectrum grow LEDs are not really white; they are blue diodes coated with a yellow phosphor, which creates the appearance of white light. Over time this phosphor coating can degrade, and the color of light it produces will change.

Full-spectrum LEDs will usually lean to the cool or the warm side, and you can use them accordingly for either foliage or flowering plants.

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Want to get a jump start on growing strawberries indoors? Look for bare-root plants you can pot up. Bare-root strawberries will arrive without any soil and bare roots - typically rubber banded together in bunches. To pot up, you'll separate each bare-root plant, make a hole in the potting mix to accommodate the roots, then gently set the plant roots into the mix and cover. Always make sure the growing crown of the strawberry plant is above the soil line. Water thoroughly.

Want to grow strawberries indoors? Look for day-neutral varieties such as alpine strawberries. Seed and plugs are available for Alpine and species strawberries. You can purchase bare-root plugs or transplants for Alpine strawberries and Everbearing (day-neutral) types.

New BOOK! Gardening Under Lights: The Complete Guide for Indoor Growers