Tips for Growing Cucumbers Indoors

February 13, 2019

There are a few tricks to growing great cucumbers indoors. Cucumbers are day-neutral, and will flower and fruit under a variety of photoperiods and you can grow them successfully with anywhere from 12 to 18 hours of light.

'Martini' Cucumber
PC: Ball Horticultural Company

If you’re growing cucumbers inside a grow tent and temperatures are warmer during the day, be sure night temperatures are cooler. Cucumbers can handle warm conditions, but perform best at temperatures between 70°F and 75°F (21–24°C). Keep plants consistently watered at all times to avoid blossom end rot.

Unless you happen to have bees buzzing around in your house or grow tent, you're going to have to do some hand pollination on your cucumber plants. Use a small paintbrush to transfer pollen from male flowers to female flowers.

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Trouble Germinating Seeds?

February 12, 2019

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.

Borage plants are prolific seed producers.
PC: Leslie F. Halleck

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

Gardening Under Lights Book


Temperature Triggers Flowering in Some Plants

February 11, 2019

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.

Broccoli going to flower in warm temperatures. The bees love it.
PC: Leslie F. Halleck

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

Gardening Under Lights Book


CFLs are Efficient Grow Lights in Small Spaces

February 10, 2019

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.

A close up of a large CFL lamp.
PC: Leslie F. Halleck

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.

Gardening Under Lights Book



Electronic Ballasts for Grow Lamps

February 9, 2019

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 Ballast
PC: Sunlight Supply, Inc.

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.

Gardening Under Lights Book



Lettuce Seeds Need Light to Germinate

February 8, 2019

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.

PC: Leslie F. Halleck

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.

Gardening Under Lights Book


Can You Grow Different Orchid Types Together?

February 7, 2019

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.

It’s fun to display blooming orchids together, but different species have different long-term temperature and humidity needs.​
PC: Leslie F. Halleck

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.

Gardening Under Lights Book


LED Grow Lamps Can Generate Less Heat

February 6, 2019

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.

PC: Sunlight Supply, Inc.

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

Gardening Under Lights Book



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