If you want to grow squash indoors with grow lighting, you're in luck! Squash will flower under a variety of photoperiods, and you can grow them successfully with anywhere from 12 to 18 hours of light; 12 to 14 hours are adequate with high-intensity lighting.

You will have to hand-pollinate indoor squash flowers. Squash and other cucurbits produce male and female flowers on the same plant. Male flowers typically emerge first, followed by female flowers, which have a swollen ovary (looks like a mini fruit) behind the flower.

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Many countertop lamp setups allow you to grow small edibles, such as microgreens, small lettuce transplants, small herbs you keep snipped, and seedlings you plan to transplant outdoors. They typically take up only 2 to 3 square feet of space, and they may fit under your kitchen cabinets.

Just remember that as plants grow and reach the lamp they may burn, so harvest herbs and transplant seedlings before they get too tall.

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Plant cuttings need slightly higher humidity as they develop new roots. Cover all cuttings with a humidity dome to keep moisture high during rooting. Don’t overcrowd: while you have to maintain humidity around the cuttings during rooting, they also need good air circulation.

Site cuttings away from intense or high levels of light, which could burn them. Bright light from a window or a couple of feet away from fluorescent or CFL fixtures will be sufficient until the cuttings have rooted.

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Some plant seeds do not germinate until they are exposed to red light. If you have ever tried to grow lettuce from seed, only to be disappointed when the seeds did not sprout, you most likely covered the seeds with soil and blocked them from the light.

Check the seed pack to see if your seeds need some exposure to light to germinate before you plant them.

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Coir is excellent for growing seedlings and mixing into the growing media for larger plants. You can use coir alone or in combination with other ingredients, or even as a hydroponic substrate.

Coir also holds moisture well for an extended period while maintaining a porous structure that drains well. I like to sprinkle a little coir on top of the soil when I'm germinating seeds, as it helps hold just the right amount of moisture for seeds to germinate successfully.

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Want to grow squash plants indoors? Standard squash plants are vines - and they can get BIG - reaching 15 to 20 feet long. Dwarf bush squash, on the other hand, will stay in the 3- to 5-foot range and are easy to keep in containers indoors.

It's always best to direct seed squash outdoors or into final container you plan to use indoors indoors. While many garden centers will offer transplants of squash plants and their relatives, these plants do not transplant well and growth is often stunted after transplanting.

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Full-spectrum grow lamps, whether they skew warm or cool, will emit some percentage of all colors of light within the PAR range. Cool full-spectrum lamps will still emit some red and yellow light, but less of it. Warm full-spectrum lamps will still emit some blue and green light, but less of it.

I can grow young tomato transplants in an open space under a large eight-lamp fluorescent fixture filled with cool-spectrum lamps. As plants grow, I replace half the cool-spectrum lamps with some warm-spectrum fluorescent tubes when I want to trigger more flowering.

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Powdery mildew is a fungal disease with fuzzy white growth. It spreads quickly, covering foliage and blocking photosynthesis, causing leaves to yellow and drop. Zinnia are particularly susceptible to powdery mildew.

Cull the herd if you have a pest or disease outbreak among your indoor plants. Consider removing any heavily infested plants in order to limit the impact on less affected plants.

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