Controlling Your Indoor Garden's Temperature
The average plant does well in daytime temperatures around 65-75°F. However, some plants prefer cooler or warmer temperatures. For example, tomatoes and peppers prefer hot weather and do best if the temperature is around 80°F during the daytime. Cool-weather crops, like lettuce and spinach, prefer cooler temperatures and can do well in temperatures as low as 45°F.
This means that if you are using an unheated spare room as your growroom, you may not need added heat if you plan to grow cool-weather vegetables. However, if you plan on growing fruiting vegetables, you will probably need an additional heat source. This may be as simple as adding a heat lamp to the mix, or as complex as using a portable heating or air-conditioning unit.
Your choice will depend not only on personal preference, but also on your budget. Another consideration that goes with maintaining optimal proper temperatures insulation. Without adequate insulation, you will require more energy to keep your growroom warm enough in the winter and cool enough in the summer.
Controlling Your Indoor Garden's Humidity Levels
Unfortunately for our plants, we prefer to keep our homes at a much lower humidity level than most plants prefer. Lack of humidity is even more of a problem in the winter, when heating our homes seems to suck every bit of moisture right out of the air. Just think about it, if we are uncomfortable, it must seem downright arid to our plants!
Depending on the size of your indoor garden, you can add moisture to the air with a pan of water in the room or just by misting your plants. If you grow your plants in pots, you can make a tray of pebbles to set your pots in. Pour water until it is almost to the top of the pebbles and add more as the water evaporates. Make sure you’ve determined the desired humidity levels of the plants you’re growing. Some crops prefer more humidity than others.
The simplest, albeit more expensive way to provide humidity is with a humidifier, and the most expensive option is an environmental controller. However, when you consider that an environmental controller humidifies and dehumidifies, you might find having one is worth the cost.
Controlling Your Indoor Garden's Ventilation
Ventilation keeps the air in a growroom fresh and the CO2 levels topped up. It also allows excess humidity to escape from the room. Address ventilation by connecting the growroom to a cool room adjacent to it through the use of either a vent in the wall or some fancy ductwork. If your set-up includes adding supplemental CO2, you need an air-tight area.
In this case, be sure to have a fan that is adequate for the size of the room to keep the air circulating properly. If your venting system is accessing the outdoors, make sure the vent has some sort of screen to keep out pests, and that you have a solution in place for unwanted odors. You’ll also want to make sure the outdoor air isn’t hitting your plants directly. Icy winter air will make for some unhappy plants.
Controlling Your Indoor Garden's Lighting Levels
Choosing the right grow lights is imperative. If you don’t provide enough light, you’ll end up with leggy, weak plants, while lighting that is too intense can burn your plants. There are many lighting systems to choose from, such as fluorescents, LEDs and high intensity discharge (HID). Fluorescent lights give off little heat but provide full-spectrum lighting that works well for most plants. LEDs also produce little heat.
They are more durable than fluorescents and their settings can be customized to fit the needs of your plants. HIDs are available in metal halide (MH) bulbs, which are ideal for flowering, and high pressure sodium (HPS) bulbs, which benefit foliage.
In terms of how much lighting your plants require, a general rule of thumb is 20-40 W per square foot of garden space. If you divide the wattage of your bulb by 20, and also by 40, the resulting numbers will give you a range of space for which the bulb will provide the proper lighting. For even more grow light optimization down the road, you should consider adding reflectors and light movers to the mix.
When you first started gardening, you probably started small, and as your confidence grew, so did your garden. The same concept applies to gardening indoors. Start simple with affordable ways to control the growing environment for your plants, and as you gain more experience, your growing environment will become an environment that grows along with your skills and knowledge.