Some seeds are more difficult to germinate than others because they have a very hard, protective seed coat. While most annual vegetable seeds do not require any special preparation for germination, seeds of some natives, perennials, and fruits require a bit of extra work, whether soaking, scarification, or stratification.

Research the plant you want to germinate to determine whether it needs any chitting, scarification, or dry or moist stratification to germinate successfully.

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Temperature can trigger flowering in some plants. As temperatures cool, respiration slows and sugar storage increases in some plants. Warming temperatures, after this period of cold, can break the dormancy.

Temperature also influences fruit set, fruit ripening, flavor, and even flower color and size.

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A CFL is a good option if you want the efficiency and effectiveness of a fluorescent lamp but prefer to use a spotlight fixture, track lighting, or other directional lamp for a group of houseplants or a single large houseplant. CFLs look like a twisted or folded-up fluorescent tube.

If you have big plants or an expansive grow area, or are growing inside a grow tent or a closet, you can use larger CFLs with light reflectors to spread the light over a larger area and quantity of plants.

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Electronic ballasts will help your lamps run cooler and more efficiently, so a significant percentage of the energy the lamp draws can be converted to usable light. They regulate both the electrical current and the frequency, thus eliminating lamp flickering.

Electronic ballasts are adjustable, so you can use them with lamps of varying wattages, which is quite handy for switching out lamps for different stages of plant growth.

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Plants that evolved to have their seeds exposed to the soil surface after dropping are adapted to germinating in the presence of light. Lettuce seeds, for example, need to be exposed to red light or they won’t sprout.

Sprinkle lettuce seeds on the surface of the soil and lightly press them down, but don’t cover them with soil. Check the seed packet for information about germination light (or dark) requirements before starting your trays.

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If you love orchids, you have probably realized you must choose your orchid varieties by their temperature preferences. It’s very tough to grow and flower different species in the same environment when they have individual temperature needs.

You can certainly display many different types of orchids together when they are blooming, but then you may need to separate them after flowering to put them back into their ideal growing conditions and light.

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When you are growing plants that need a more concentrated delivery of light (such as seedlings), the closer you can place your lights without burning them, the better. Smaller LEDs generate less heat than other grow lamps and can be placed closer to your plants. Lower heat output with heat emitting from the back of the fixture means less heat directed to the canopy of your plants.

But keep in mind that larger LED rigs can still generate heat, especially in enclosed growing spaces.

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Dual-band LEDs that mix primarily red and blue light produce light that looks pink to purple in color. You can use this mixture for continuous growth through vegetative and flowering stages.

You can also use single-band nanometer-specific blue LEDs for vegetative growth, then add red if your plants need to flower. Or bulk up young vegetative plants using single-band red LEDs, then add in blue light to encourage flowering.

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