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What's Growin' On Stony Brook

“ On every stem, on every leaf,... and at the root of everything that grew, was a professional specialist in the shape of grub, caterpillar, aphis, or other expert, whose business it was to devour that particular part. ” ~ Oliver Wendell Holmes

Who hasn’t looked over their houseplants and observed little cottony looking clumps in the leaf corners, or little gnats flying around the soil? Have you ever flipped over some foliage to find little scales on the undersides and pale, yellowish, growth, or webbing surrounding a speckled stunted sprig? But they looked so good just a few short weeks ago, right?

Absolutely! Here’s why;

In the nursery or outside, your plants are exposed to the washing waters of rainfall or daily hosing in the greenhouse, the predatory insects and applications that keep the bad guys at bay, and the perfect amounts of sunshine and food that keep plants thriving. We drag them inside and steal their sunlight hours behind curtains and walls. We turn our oil or gas heat on, drying out the moisture that kept their leaves supple and soil damp. They are existing without the help of trained growers that recognize disease and insects. And at the end of the day, we can’t understand why they are performing so poorly.

In this article I will discuss some of the common insects that rob our plants of vigor and vitality, indoors and out.

The Common Insect Culprits

aphids Aphids
Very small, sap sucking insects that resemble miniature grasshoppers. You will usually notice them first at the unions of the stem and leaf, then along the petiole, and eventually on the leaf and the entire plant, gathering mostly on the new growth. They suck the sap from the leaf causing a pale appearance which leaves a shiny residue on the plant leaf called honey dew, a telltale sign of feeding.

scale Scale
Another large group of sap sucking insects that excrete honeydew. You will most likely notice shell like bumps on the undersides of the leaves and on the petiole/stem attachment. One species is responsible for the white, cotton like masses you find on your indoor and outdoor plants which are actually the insects’ egg masses.

fungs gnats Fungus Gnat
Fungus gnats are small, delicate bodies flies that live within the first 2-3” of soil. Their larvae feed on the plant roots, algae, and fungi.

spider mites Spider Mites
Actually members of the arachnid family and are easily distinguished by their telltale webbing and stippling. A healthy plant will quickly show dull brown leaves and what looks like cobwebs will form around plant sections. A healthy female can lay 20 eggs per day, one of those offspring’s can reach sexual maturity in 5 days.

Waging the War

The easiest and safest way to manage these guys would be a cycle of applications of horticultural oil which can be found at your garden center or home improvement center. They are oil based products which smother or interrupt the feeding of soft bodied insects. You can also mix up two tablespoons of vegetable oil, two tablespoons of dishwashing soap, and a gallon of water for a homemade insecticidal soap spray. If the infestation has gotten significant you can also purchase a systemic insecticide or pesticide spray. Whichever application you choose, be sure to apply it on a weekly basis for at least three weeks to control all of the insects life cycles.

Additional Tips

Try to keep your plants moisture levels up by incorporating a moisture dish and even think of supplementing the light source with a grow light on a timer. A healthy plant can withstand insects and disease attacks well than a weak one.

Tags: Grow Red

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