Growing your vegetables and herbs indoors can be very productive and enjoyable. Like any organic food growing, the tactics you apply can have a profound impact on your success.
Indoor food growing will protect your plants from larger animals, but not from insects. Indoor plants are likely to suffer from the lack of natural biological controls, that is, the predators that would keep plant insect pests in check in a more biologically complex outdoor environment.
The major insect pests indoors are: aphids, scales, white flies, mealy bugs, and mites. These all produce honeydew. The insects usually enter the home or indoor area on a plant or are brought in with garden materials. You can use this web site to help you identify which of these pests are affecting your plants.
Pest management tactics
Physical - When a few bugs appear: hand-pick, squash, or rub them off. You must be observant each day to be successful with this as leaving things for a week could mean the end of the plant. Washing the plant off in a mild soapy water may also help, but be sure to not make a mess inside.
Move the plant outdoors – At different times of the year, depending on your climate, there will be plenty of general insect predators and parasites in your garden, putting the afflicted plant outdoors for several weeks may take care of the problem. When moving plants infested with honeydew producers outside, you might wish to place them on stands with ant-excluders around the legs so that ants don’t prevent the aphid predators and parasites from doing a good job.
Introduce predator insects indoors - For bug-infested plants that are too large to move, hand-pick, or hose off, you can import predatory insects. After cleaning up the pest insects the predators will die off from lack of food, so for each new outbreak new predators will have to be imported. This web site is a great resource for suppliers of predator insects and linking which predators relate to aphids, scales, white flies, mealy bugs, and mites.
Organic insecticides - If you have exhausted all other methods of insect management, then be sure to select the least toxic material that will do the job. Move the plant outdoors if possible, and wear a mask and gloves while handling the insecticide and treating the plant, washing yourself and your clothes afterwards. This Australian site provides a list of well known organic products that deal with the aphids, scales, white flies, mealy bugs, and mites
Plant disease management tactics
Plant diseases are harder to cure than insect infestations, some tips are provided below which are primarily preventative measures:
Do not over-water – Too much water will promote mould and turn the soil anaerobic. Closely monitor soil moisture levels. You may choose to have a wicking system with your indoor beds which will recycle water and allow consistent moisture levels. Here is an example of an Australian company selling well designed wicking systems into timber garden beds.
Do not over-fertilize - Excess nitrogen may encourage aphid infestations indoors, in addition to creating weak, over-succulent plants more susceptible to disease. Use a blend of liquid organic fertilisers and apply no more than monthly. My preference is to supplement these with biodynamic preparations bi-monthly, such as soil activator.
Maintain optimum temperatures for plants to grow – If its too hot or too cold they will not thrive, lack vitality and be more subject to disease. Our web site subscriber area provides optimum average temperatures for all common vegetables to thrive. Humidity is an important factor and if the indoor climate is too humid, you will encourage mould. In this case, use a fan to create airflow or open a window.
Cut out infections - Leaves infested with mould or fungus leaf-spots can be cut off.
Crown stem or root rot - It is best to destroy the plant. Avoid the problem in the future by not over-watering or over-fertilizing, and by keeping water off susceptible plants.
Improve observation skills – Concentrate on developing your observation skills so you can know when the plants need help. This is getting in-tune with the plant and its very possible if you spend sufficient time observing the plant and objectively thinking through how it responds to changes. A green thumb could evolve from these observation skills.
Replace soil – If you are not solving the disease problem, the last resort is to replace the soil in fresh material. I feel its helpful to get into the rhythm of replacing soil used in pots for food growing each year and try composting that soil so you bring life into it and then use that “refuse soil” next year in rotation.
You will find detailed information on pests and disease management of vegetables, herbs and fruit trees in our web site subscriber area on 300 food crops. In our biodynamic gardening courses, we do concentrate on biodynamic methods of pests and disease control.
Author – Peter Kearney – www.cityfoodgrowers.com.au