Gardeners and farmers know that healthy soil means healthy plants. Those of us who eat what we grow also understand the improved taste, nutritional value and shelf life of produce that comes from healthy plants. It is easy then to understand how the health of our soil might affect our personal health.
Today, people are more aware of the effects of conscious food consumption on their health and most of us are making choices that offer health benefits. Certainly, avoiding sweets and fatty or salty foods is a step toward avoiding diabetes and heart disease. Some consumers also prefer to buy organic foods to help them avoid toxic chemicals that may remain on food products from nonorganic farms. More and more people are also becoming aware of the nutritional losses that occur over time and are choosing to buy locally grown food directly from farmers when possible. Implementing these habits can definitely lead to better health.
If you eat what you grow, or sell food crops that you grow, you may be interested in research showing the increase in nutritional value of foods grown in healthy soil. Many researchers have found that by analyzing your soil and you can make soil improvements that will improve the nutritional value of the food you grow, which can have positive health benefits.
Vibrant, healthy soil is where it all begins. Organic agriculture pioneers like Robert Rodale knew the nutritional value of food is affected by the way it is grown and the condition of the soil in which it is grown.
Harsh agricultural processes and chemical herbicides and pesticides deplete soil of its naturally occurring minerals and vital microorganisms. Depleted soil can’t impart the maximum amount of nutrients possible to our food. Research has shown growing plants in healthy soil increases the nutrient density in the crop. It follows then that the more we improve the health of soil, the more nutritious our food will be.
Another result of growing edible plants in healthier soil is it enhances flavor. Raspberries taste sweeter. Tomatoes, peppers and herbs have more flavor. Top chefs today seek the freshest ingredients from organic farms or those using sustainable practices. They want to serve the tastiest food possible.
Those familiar with the soil food web know healthy soil depends on a large and complex community of organisms thriving in soil and interacting with the environment as well as other plants and animals in your garden. Soil organisms thrive in natural settings so the better we can imitate the forest or other natural settings on our farms or in our gardens, the healthier our soil is likely to be.
Plant scientist Jana Bogs has taken this knowledge and research to the next level and recommends a program of soil testing and soil improvement with emphasis on increasing the nutritional value of your crops.
She has designed a system to create ideal soil for growing the best nutritional quality food possible, thus maximizing its health benefits. Bogs’ system begins with analysis of the soil and plant tissue and ends with nutritional research results of plants grown in soil augmented to produce nutrient-dense crops.
The Kona County Farm Bureau is sponsoring a two-part series by Bogs Nov. 17 and 18. “Soil: from the Ground Up” will address testing the nutritional value of crops and ways the tests can reveal techniques for soil improvement. In the Nov. 17 session, “Healthy Soil = Better Crops,” participants may bring plants or crops for field testing including brix. On Nov. 18, “Creating Healthy Soil” will include a presentation and hands-on demonstration of ways to use test results to select and apply amendments that can improve your soil’s health. The classes will be held at Tropical Edibles Nursery in Captain Cook.
More information on the classes is available by calling 328-0420 or writing tropicalediblesnursery@gmail.com. Information on Bogs’ system is available at beyondorganicresearch.com.
Tropical
gardening helpline
Tony asks: The leaves on my cactus have twisty silver trails on them. What could it be and what should I do about it?
Answer: The twisty trails you describe are probably caused by leaf miners. They are the result of the feeding pattern of the larva of a small insect in the genus Liriomyza. Many species exist that attack different host plants, but all the larvae leave similar distinctive trails.
Plants that have been overwatered or overfertilized are more susceptible to insect attack. Try to give your plants only the amount of water and nutrition they need to prevent problems.
The life cycle of a leaf miner begins when the adult lays eggs on the leaves of the host plant. The larva emerges and feeds on the tissue between the upper and lower surfaces of the leaves creating the distinctive trails.
Once they have eaten and developed to maturity, the larvae leave the “mines” they have created and drop to the ground to pupate. The cycle takes about two weeks to complete. Interruption of this cycle at any point will help to reduce the infestation.
Removing affected leaves as soon as you see them can get rid of the existing miners before they pupate into adults. Placing plastic trays under affected plants to collect and destroy the pupae is another way to arrest their life cycle.
If damage becomes severe, you may want to prevent the adults from laying eggs by spraying a low-toxic insecticide like one containing neem to kill the adult fly.
Systemic insecticides can help control the larvae but should only be used on ornamental plants. If you want to encourage the predator, a small parasitic wasp, to come feed, it is best not to apply any insecticide.
Since your infestation appears to be severe and is probably affecting the plant’s ability to photosynthesize, you may want to bring in the big guns. Several systemic insecticides are labeled for use on leaf miners. Those such as Orthene, containing acephate, or Bayer Advanced Tree and Shrub Insect Control, imidacloprid, may be used to get rid of your leaf miners but you will probably want to trim your plants way back to remove the damaged areas.
Email plant questions to konamg@ctahr.hawaii.edu for answers by certified master gardeners. Some questions will be chosen for inclusion in this column.
Diana Duff is a local organic farmer, plant adviser and consultant.
