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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Garlic needs a specific temperature and photoperiod combination to form harvestable bulbs, which makes it a bit trickier to grow indoors.

Garlic is not only photoperiodic, but it also requires vernalization to form bulbs. This is why you must plant garlic cloves in the fall, then harvest the following spring or summer. You may find garlic a tough crop to crack if you try to grow it indoors at consistent temperatures and photoperiods.

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Root plugs are typically made from hydrophilic, or water-absorbent, polyurethane foam. Biodegradable organic root plugs are also available.

Root plugs are often inoculated with beneficial microbes to help seeds and cuttings get off to a great start.

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Simple lamp timers, or more sophisticated digital timers, can be used to turn your grow lamps on and off on a set lighting schedule. Timers make it easy for you to deliver the right duration of light, or photoperiod, to your plants.

A quantitative short-day plant may bloom earlier or better if it has longer nights. A quantitative long-day plant may bloom earlier or better when given shorter nights. Both plants will eventually flower, however, even if the photoperiod is not ideal.

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These cucumber plants were started from seed at the same time. The container on top was grown under a CMH lamp with a higher PPFD, while the container on the bottom was grown under a CFL with a lower PPFD. The plants grown under the higher-intensity lamp are far ahead of those grown under the lower-intensity lamp.

Typically, the higher the PPFD delivery of a grow lamp, the more expensive it is. You can run a less expensive lamp with a lower PPFD value for a longer photoperiod and rack up the same DLI that your plants need. Just be sure not to run the lamp longer than the plants can tolerate.

You can also choose a more expensive lamp with a higher PPFD and run it fewer hours to deliver the same DLI. Provide a long enough photoperiod if one is required.

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Standard citrus trees can grow 15 to 20 feet tall. For indoor gardening, it’s best to stick with dwarf types that you can maintain at 3 to 6 feet tall.

Dwarf lemon varieties for indoor growing include: 'Dwarf Meyer’, ‘Dwarf Meyer Improved’, ‘Eureka’, ‘Variegated Pink’, and ‘Ponderosa.’

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