There is a war being waged against our beloved plants and trees and sometimes their own natural defenses get overpowered. In an increasingly health-conscious world, people are looking for natural alternatives to controlling specific plant diseases in lieu of chemicals that kill everything without discretion.
Here are four common problems gardeners face and natural remedies they can try.
Aphids are small parasitic insects that can wreak havoc on fruit trees, vegetable gardens, ornamentals, shade trees and most shrubs. Aphids, which are sort of pear shaped with long antennae and two backward-facing tubes protruding from the abdomen, are prolific reproducers and voracious eaters. That is how—unless you keep a sharp eye out—they can nearly destroy a plant before you even realize it is infected.
Adult aphids and their nymphs suck the life-giving sap from the leaves of the plant. When a colony of aphids feed on a plant, in addition to the obvious damage inflicted by their feeding, they leave behind a sticky, honeydew-like substance, creating prime conditions for mold to grow on the leaves and the fruit.
Twisted and distorted leaves are common on aphid-infested plants and the fruit produced is often deformed and much smaller than normal. Badly infected branches and leaves may eventually drop off.
Fortunately, there are a variety of natural remedies at our disposal to combat them, including other insects such as aphid midges, wasps and ladybugs. This article focuses on the aphid midge, which lays its eggs amongst the aphids.
The eggs hatch after two or three days and the larvae feed on the aphids for up to five days before they get the hardwired signal to bore into the ground, where they pupate. About two weeks later, they emerge as adults and the cycle resumes.
If you’re buying aphid midges, purchase 200 to 300 cocoons for a backyard garden or greenhouse. Place three to five cocoons per plant and five to 10 on each of your trees, depending on their size. To attract wild aphid midges to your garden, plant pollen-producing and nectar-producing flowers around your trees or garden in an area slightly sheltered from wind and make sure water is available to them.
Another control measure is spraying plants and vegetables with water forcefully enough to wash the aphids off of the leaves. Rinse the smaller plants more frequently and be sure to rinse the undersides of the leaf.
Brown Rot Fungus
Fungus is a common problem facing plants of all types, especially fruiting trees. Some fungus is necessary and actually beneficial to certain plants, but other types, such as the type that causes brown rot, can have a devastating effect on your garden. Fruit infected with brown rot begins to display small brown spots that spread quickly and eventually cover the entire fruit with brownish-gray spores.
Mummified fruit is the end-result. When available, plant fungus-resistant cultivars. Additionally, prune or remove the visibly damaged fruit from the tree. This allows for better air circulation, creates a drier environment and reduces the chance of reinfection. After blossoming, spray the plant with a sulfur solution and then again before harvesting to prevent brown rot from occurring in storage.
This is another problem brought on by fungus and generally affects potatoes and tomato plants. Early blight is just what the name indicates—a blight that appears on the leaves of the plant early in its development. Signs of early blight appear as small brown spots that begin to spread rapidly, eventually covering the entire leaf and spreading to other leaves.
Use disease-free seeds and seed potatoes and practice crop rotation. Clean up any old plant debris that may harbor the fungus. Remove all highly infected plants and destroy them. Additionally, the use of organic, copper-based fungicides can help stop the spread of this fungus-based disease.
Just as the name implies, black spot fungus appears on the leaves of rose bushes as small dark spots circled by a yellowish tissue. Black spot is moisture driven and can also infect the stems of the rose, causing black, purplish blisters on young stalks.
Once started, black spot is difficult to control, but there are measures one can introduce to reduce the risk of infection. Avoid getting the leaves wet when watering and keep plants well pruned to encourage airflow.
Removing the infected leaves and stems is paramount. You may also spray your plants early on with a sulfur solution. Another natural method gaining in popularity is spraying your rose bushes with a solution consisting of 1 tsp. baking soda to 1 qt. water.
The list of insects, fungi, diseases and natural disasters that besiege our plants daily is virtually endless. This article, however, is not. In closing, it is my hope you have been informed, enlightened and perhaps encouraged by some of what you have read here. As a gardener myself, I truly wish you every success, wherever your green thumb may take you!