Hydroponic Growing Systems

December 27, 2018

Many indoor growers choose to skip the soil and grow their plants in hydroponic, aeroponic, or aquaponic systems. While growing hydroponically will reduce some of the pressure of checking your plants daily for water needs, you will have monitor the system.

A large grow tent set up with an ebb and flow hydroponic bucket system for multiple large plants.
PC: Sunlight Supply, Inc.

The most common form of hydroponic system is the nutrient film technique (NFT), which involves growing plants with their roots directly suspended in water. Other methods include wick, water culture, ebb and flow, drip, and aeroponics.

Gardening Under Lights Book!


Seedlings Will Stretch if Too Far From Light

December 26, 2018

The light source must be very close to your seedlings as they germinate, as near as 3 or 4 inches from the seeds as they emerge from the soil. These tiny seedlings are too far from the grow lights above – they will soon become too stretched if not moved closer to the light.

PC: Leslie F. Halleck

Ratcheted cords or chains that allow you to move light fixtures up and down will enable you to place your lamps very close to seedlings as they are just emerging, then lift the light source as they grow.

Gardening Under Lights Book


Speed up Seedlings with Heat Mats

December 25, 2018

If you are growing warm-season crops—such as basil, tomatoes, or peppers—from seed indoors during cold winter months, you must warm their soil. Ultimately, your goal is to get as many seeds to germinate as quickly as possible. For crops that need warmer soil temperatures, especially when you’re starting them indoors during colder months, a seedling heat mat can speed up the germination process and ensure success.

A heat mat warming up the soil for new seedlings.

A heat mat warming up the soil for new seedlings.
PC: Leslie F. Halleck

Heat mats, which are placed directly under your seed tray, can warm soil to an average of 15 to 20 degrees Fahrenheit above room temperature. Be sure to use a heat mat specifically designed for seed germination. Seedling heat mats are insulated and moisture-resistant, so you can place them on normal surfaces under your seed trays.

Gardening Under Lights Book


Haworthia Houseplant

December 24, 2018

While many succulents can't be grown long term indoors, due to a lack of light, there are some species that can tolerate indoor growing without grow lights. When you're gardening under lights indoors, it's good to know which plants can tolerate lower light conditions.

A potted Haworthia
PC: Arizona East

Haworthia are one type of succulent that can tolerate lower lighting, and can be maintained in a bright windowsill. Haworthia are compact succulents that grow in a whorl of foliage. Their shallow root systems make them perfect for keeping in small pots as easy-care houseplants.

Gardening Under Lights Book


How Far From Grow Lights to Place Seedlings

December 23, 2018

A smaller two- to four-lamp fluorescent fixture can sit just a few inches above young seedlings. As plants grow larger, move the fixture a foot or so higher. Large fluorescent fixtures may need to be 2 to 3 feet above plants to avoid causing heat stress.

PC: Leslie F. Halleck

I use a large adjustable shelf with 4-lamp T5 fixtures to start seeds, grow microgreens, transition transplants. You might find large fixtures like these can get pretty warm so you may not need a seedling heat mat, or you can remove one or two bulbs to reduce light and heat load if it seems your young seedlings need a bit less of either.

Gardening Under Lights Book



Where to Take a Plant Cutting

December 22, 2018

Plants have varying requirements for how, where, and when to take cuttings, the ideal size of the cuttings, and how long they may take to root. Some plants, such as succulents, will root from the base of a leaf. Others, like begonias and African violets, will root straight from the leaf surface.

Baby African violets from leaf stem cuttings.
PC: Leslie F. Halleck

Many perennials are propagated by taking root cuttings or divisions. You can propagate certain tropicals, such as pothos ivy, by setting a stem in water for a few weeks.

Gardening Under Lights Book


Ideal Temperatures for Growing Broccoli

December 21, 2018

Calabrese and broccoli are cool-season crops, and temperature controls flowering responses; most do not handle heat well. Flower heads can also be malformed or damaged if young transplants sit at temperatures below 40°F (4°C) for a few weeks.

PC: Leslie F. Halleck

The ideal temperature range for happy broccoli is between 65°F and 80°F (18–26°C). This can be tough to maintain in an enclosed grow room or grow tent unless it is air-conditioned, but normal household temperatures might be adequate.

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


Oedema Blisters on Indoor Pepper Plants

December 20, 2018

Not technically a disease, rather a physical disorder related to water and humidity management and types of light, oedema blisters can cause defoliation.

PC: Leslie F. Halleck

Oedema occurs when roots take up water faster that the plant can use it. Once water pressure builds up enough in the plant cells, they burst, leaving visible blisters.

Gardening Under Lights Book


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