Plants that do not require an exact photoperiod before they are triggered to flower, but will bloom faster or better with a specific photoperiod, are classified as quantitative, or facultative. Lettuce is a classic quantitative long-day plant.

While you might start your tiny lettuce seedlings under a long photoperiod of 16 hours, if you continue growing them indoors you must reduce that lighting period to 12 to 13 hours after you transplant the seedlings into their final container. If you continue growing them under 16 hours of light, the plants may bolt and go to flower too early, ending your harvest.

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Collecting and saving seeds from the plants you’re already growing is a sustainable approach to your gardening endeavors and a smart way to save money.

Dry seeds are easy to collect and store. Once you have harvested the seeds, leave them on a towel in a cool, dry place for a few days to ensure they are completely dry before you store them. Place them in a sealed container—such as an envelope, a paper seed packet, or a jar—and store in a cool, dry, dark place.

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The light produced by CFLs is acceptable in your open living spaces. CFLs are a good lighting solution for smaller spaces, small grow tents, and areas where you do not want too much heat buildup.

Most CFLs are full spectrum, leaning to the cooler side, but you can also find them with a warmer Kelvin color-temperature rating.

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Light-emitting diode (LED) grow-light technology allows you to narrow the spectrum of light you provide to just one color, referred to as nanometer specific light. You can purchase LED grow lamps that emit only a red spectrum of light or a blue spectrum of light (as well as other individual colors, such as orange and green).

While you can use red and blue light exclusively and successfully, only a few species of plants are able to grow well under only red or blue light indefinitely.

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Root crops (carrots, turnips, beets, radishes) and large- seeded crops (beans, broad beans, squash, corn) do not transplant well, so you should sow them directly into the garden or final growing container.

In this case, the days-to-harvest number on the seed packet is the time it will take to harvest from the date of germination. Plant these crops when indoor or outdoor temperatures are ideal.

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Large LED rigs run relatively quietly (although they do make noise), might not use as much electricity as HID lamps, may produce less heat (they claim to convert more of the energy into light), and provide a large footprint of lighted growing area.

These features make true full-spectrum LED fixtures useful for growing in an open living space where you don’t want pink- or purple-colored light. Be prepared for these fixtures to make some noise and carry a heftier price tag than other LEDs.

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There are many different types of orchids you can grow indoors. Vanda orchids are particularly beautiful, but can sometimes be a little challenging for new orchid keepers.

Vanda orchids require high humidity in order to thrive. Wetting the growing medium—as opposed to directly watering roots like you might with terrestrial-type plants—increases the humidity around the root zone and leaves. Epiphytic types with aerial roots will appreciate a regular direct misting of foliage and roots (not the air around them) versus heavy watering at the root zone.

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

It is important to increase humidity around your seeds as they are germinating. The easiest way to accomplish this is to place a humidity dome on top of your seed trays. A good humidity dome comes with a vent you can open and close to conserve or vent moisture and heat.

Remove the dome once all your seedlings have germinated and begin to produce green growth. If you keep it on too long, fungal diseases or rot could set in. While young seedlings need to remain moist, excess moisture can promote damping off disease, which causes seedlings to rot at the soil line and topple over. Too much humidity also encourages powdery mildew on young seedlings and transplants.

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