Starting an indoor vegetable garden (sometimes called kitchen or container gardening) can provide you with vegetables that grow quickly and full. Whether you are growing indoor vegetables to keep the yield small, or are growing them directly from seed in order to transplant in your outdoor garden, it is important to plan well. You will find that your plants will thrive, have more nutritional value, and even taste better in the right conditions!
Most vegetables require 6-8 hours of sunlight a day, so choose a sunny spot where the sun will directly hit your indoor vegetable garden. Windows facing south, southeast, or southwest work best. If you don't have this kind of sunlight in your indoor garden space, you can combine both natural and artificial light. To create the best artificial light, use full-spectrum fluorescent lightbulbs and hang them above your vegetable garden, or firect from both sides for good coverage. Lighting and timers can be set up to automatically provide the light required. One source of direct sunlight is adequate for smaller plants (that will later be transplanted in your outdoor garden) as long as it is full sun for 6-8 hours.
Your indoor vegetable gardening space will need to have good air circulation but not be drafty. Choose an area of your home that is generally warmer. A regular room-temperatures can fluctuate between 15-25°C. The cooler temperatures are ideal for the leafy green vegetables (lettuce, cabbage, spinach, etc) and warmer temperatures for the heat-loving vegetables (such as peppers, beans, and tomatoes). Plot out your vegetables according to the temperature they prefer.
Do not use soil from your outdoor vegetable garden. There are two standard choices for growth mediums; (1) modified garden soil, or; (2) soilless.
Modified garden soil should be mixed to contain approximately 1/3 garden soil, 1/3 peat moss, and 1/3 coarse sand. If a plant (like herbs) requires less retained moisture in the soil, simply add more sand to the mixture and less peat moss. Modified garden soil is heavier than soilless growth mediums and can contain disease, insects, and weeds.
Soilless growth mediums are typically lighter than their garden soil counterpart. A good soilless mixture will contain ~40% peat moss, ~20% pine bark, ~20% vermiculite, and ~%20 perlite or coarse sand. Soilless mediums can be used for multiple vegetable growing seasons, but the organic materials will eventually breakdown, loosing aeration and drainage. Replace at this point.
Most vegetables need at least 4 inches of depth for the roots to grow (carrots are an obvious exception). Almost any kind of container will work, as long as it is clean, is at least 4 inches deep, and has drainage holes in the bottom. Growing flats from your local garden centre work well too, especially for lettuce and micro greens. If your pots do not already have drainage holes at the bottom, be sure to create them by poking 3 or 4 pea-sized holes into the bottom of the container.
Small containers should probably be avoided because they usually don't hold enough water, or have enough room for the plant roots. Although clay pots are usually selected for esthetic reasons, it is better to use plastic containers because they retain more moisture. Ideally you should place your individual plant pots or growing flats into a tray lined with pea gravel or small stones. These trays will hold the run-off water and hold the plant pots upright.
Over watering is the most common cause of death for indoor vegetable garden plants, and under watering them is the next! It is crucial to follow a careful watering routine for your indoor garden to maintain the proper growing conditions. Without natural watering from the rain or night moisture, indoor plants dry out quickly. Your set-up of the large gravel trays that hold the run-off water will provide the biggest advantage here. As a general rule, plants need less water during the winter months and more during the late spring and summer. Allow the soil to go slightly dry to the touch at the surface of the container between watering. In very hot weather you may need to water twice a day, and regularly check the soil. If you suspect over-watering, check to see if water is pooling and not draining out the bottom of the container. You may start to see mould on the surface or root rot at the bottom of the container. If you have under watered, the containers will feel extremely light in weight and the soil will be dry and light in colour.
Actively growing plants in a pre-mixed soil requires fertilization once every 6-8 weeks. You can use timed-release fertilizer pellets that release nutrients to the soil each time you water. Some gardeners use water soluble fertilizers such as these organic ones -- fish emulsion or seaweed fertilizer -- or chemical based products. Whichever fertilizer you choose, do not over fertilize as it can cause salt buildup and burn the delicate roots of indoor garden plants.
One of the advantages of growing an indoor vegetable garden is that there are fewer pests to worry about. If you have other house plants you may have mealy bugs, spider mites, aphids or whitefllies, but these can generally be controlled with organic insecticide soap found at your local garden centre. Follow the directions on the soap package and do not overuse or spray plants too close to harvest time. If you choose not to treat your indoor gardening space with organic insecticide, remember to wash your produce before eating it.
Once you have your indoor garden space set up, you can plot out what you want to plant and where you will plant it according to the growing conditions each vegetable needs. Some important recommendations in choosing what to plant in your indoor garden are to (a) start simple and small, and (b) start with the vegetables you like to eat, and vary it as you learn more.
Here are some of the vegetables that are to easy to grow indoors: