A greenhouse is a good way for an amateur gardener to experiment with and cultivate new plants. It's also excellent for starting seeds early, protecting plants to be used for propagation, and potentially increase the variety of plants cultivated. Choosing to build a cement foundation greenhouse complete with air ventilation systems can get a bit complicated for the gardening beginner so it is recommended you turn a warm, sunny room in your house into a greenhouse before expanding to an entire greenhouse addition. Old tabletops, work benches or shelves are perfect for such indoor gardening experiments.
Choose an area of your house that gets at least six hours of direct sunlight each day. Sunny bay windows that face west or south are ideal. If you do not have such a window purchase grow lights, which simulate sunlight and allow more options as to where to create your greenhouse. Grow lights can be purchased at your local garden supply store.
Purchase a shelving kit at your local garden supply store if you do not have any old tables or work benches to use in your greenhouse project. Consider buying a plastic shelving unit that is lightweight and easy to clean. Measure the area you wish to use before making any purchases.
Choose an upstairs room for your greenhouse if using grow lights and consider placing plants on shelves for maximum heat as heat rises. Be sure to suspend grow lights as close to plants as possible and place lights 1 or 2 inches from soil if growing plants from seeds. Not doing so will result in seedlings that are tall and spindly as opposed to stocky and healthy.
Place a vinyl cover if desired over plants/seeds to retain moisture and heat. If the room you choose for your plants is warm enough (75 to 90 degrees F), such covers may not be necessary. Open windows if the weather allows to provide adequate ventilation or consider placing a fan set on low to circulate air.
Water plants when soil is dry only with room temperature water to maintain plant health. As greenhouses are climate-controlled environments, over-watering can kill plants and seedlings very quickly. Some greenhouse systems use drip irrigation to maintain a certain level of watering.