Article 2-3 Designing and Indoor Garden

We plan indoor gardens for the crop-and the gardener! Plants have specific needs for fast growth and great crop yields-light, water, food, temperature, C02 and so on-and we must keep these requirements in mind when planning a garden. But gardeners have needs too-the ability to reach all the plants, for example-and a well-planned garden must consider the grower as well as the plants. If it’s very difficult for the gardener to do his job, chances are that it won’t get done! Consider locations of doors, traffic patterns, the best location for the exhaust fan, where to put the reservoir-all this information will guide you in laying out a practical efficient garden. We look at directional air movement first, since the exhaust and intake fans often require modifications to the building-holes in the wall for exhaust ducting, connections to a chimney, and so on. In general, air movement should be in a straight line: from the intake source, through the plants, toward the exhaust fan and out of the garden. Directional air movement helps keep temperatures and humidity levels correct, supplies C02 to the crops, helps crops take up fertilizers and keeps down bugs and disease problems!


A. Air Intake Source

Purpose To supply new, room-temperature air to the garden.
  • Fresh air from the intake source is an important source of C02 when gardens are grown without C02 enrichment.
  • Fresh air supply helps maintain a correct garden temperature by replacing the hot air under the lamps with mild (21°C=70°F) temperature air from intake source.
Means of supply: intake fan or vent.
Location: At one end of garden, usually at the opposite end from the exhaust fan system.
  • Fresh air from the intake source is an important source of C02 when gardens are grown without C02 enrichment.
  • A mild intake temperature is important: cold intake air can harm crops, hot air can’t cool the garden.
  • The intake source can be a possible entry source for pests and disease especially if fresh air is brought in from out of doors. Use ‘No- Pest’ strips to discourage “home invasions” by pests.
  • The best source for air intake is another room in the building.

B. Oscillating Fan (s)

Purpose To move air from the intake source through the plants.
  • Makes C02 available to crops.
  • Helps maintain correct garden temperatures.
  • Removes hot, humid air from crops, maintaining proper humidity levels in the garden.
  • Aids crops in moving water and nutrients up from roots for use by the top growth.
  • Helps discourage pest and disease problems.
Location: Near crops, at ‘intake’ end of grow room.
  • Fans should be mounted level with the height of the plants.
  • Stand fans or wall mount fans are best.
  • Position fans to move air evenly through the crop, towards the exhaust fan.
  • Avoid blowing strong winds on new transplants-raise fans to blow air above the plants until root systems are established.
  • Use all fans for 24 hrs/day if possible.

C. Exhaust Fan and Ducting System

Purpose To remove hot, moist air from the garden.
  • Helps maintain correct garden temperature.
  • Helps maintain correct humidity levels.
  • Helps replace C02 levels for crop.
  • Helps discourage disease and pest problems.
Location: at far end of the grow-room from the fresh air intake source.
  • Mount exhaust fan at height of the crop or slightly higher.
  • Consult retail supply store staff for advice on fan size and strength for your own garden.
  • Use the exhaust fan 24 hrs/day if possible.

Now let’s consider lighting, since it is generally installed before the garden system is in place. Decide on the area you’ll be lighting, whether you’ll be top lighting or ‘broad siding’ your crops, and how many lamps, reflectors, etc., will be needed. Make it easy and simple to raise and lower your lamps, so you can change the height of your lights as your crops grow.