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Beginner’s Guide To Gardening: Disease Control

Even the best-loved plants can get infected by disease. Here are organic tips and tricks to apply to your garden to keep your crops healthy.

Diseased Leaves

Photo: Dianne Venetta

Leaf miners attack this tomato plant, leaving it susceptible to infection.

What are those spots on my leaves?

Is that normal? Are they supposed to be there? Quickly leafing through the pages of your garden encyclopedia, you check for photos displaying similar markings – anything that might give you an indication as to what this horrible infection could be.

Uh, oh. Found one. Scanning the description, you learn you have some sort of fungus. Ugh. Now what? I’m organic. I can’t spray anything on my vegetables – I have to eat those things!

The Organic Dilemma

You’re quite right. Be very careful what you spray on your plant, because what you spritz on your leaves you may as well spritz on your tongue, practically speaking anyway. One of the reasons we garden organically is to avoid toxins.

While efficient at killing the targeted disease, commercial sprays are loaded with chemicals that can also do a number on humans, albeit in a slow, gradual sort of way. You see, while scientific evidence can’t always pinpoint exact connections between one chemical spray and its ill-fated health effects, it can suggest they exist.

And if you can eliminate, or at least minimize, disease in your plants with natural methods, wouldn’t you do so? Even if it means a bit more work on your part? Of course you would! You’d do anything to protect your health and the health of your family. (Why, even your beloved pet can get sick!)

Soggy Plants Are Unhappy Plants

But where does one begin with organic disease control? If you can’t spray the problem away, what can you do?

Organic disease control begins with prevention, and believe it or not, proper watering techniques go a long way to help matters. Problems like powdery mildew and root rot occur because of moist conditions. In humid areas, it’s an even bigger problem, because moisture hangs in the air.

I see your shoulders drooping and I know what you’re thinking: how do you prevent humidity?

You don’t. What you can do, is water your plants with a concoction of compost or manure tea. Not only is this mixture a great source of plant food, it can also help fight off many plant diseases by inoculating plants with beneficial organisms.

Kitchen Solutions

Neem oil is another proven method for controlling disease, particularly early blight and rust (those red, yellow and/or orange spots on your leaves). Baking soda spray is another old-fashioned remedy that has proven successful in prevention.

Keep in mind that disease can spread fairly quickly, so you’ll want to remove affected leaves immediately to prevent further infection.

Plants Help Themselves

As mentioned in a previous article, marigolds are a great flower to plant in and around your garden. Not only do they repel many insects, they deter underground nematodes that can assist in the destruction of your plants by root rot.

Also, maintain proper spacing between your plants to allow good air flow. This will help in reducing much of the problem, in addition to the tried-and-true practice of crop rotation. Remember: some diseases can linger in the soil and affect next season’s crop, harming your plants before they ever get thoroughly underway. A ghastly proposition, to say the least!

The Power Of The Sun

In between seasons, consider solarizing your soil. This is the process by which you cover your beds with plastic paper and allow the sun’s heat to penetrate and warm the soil to temperatures that will kill pests and disease.

But plan ahead, because it takes a good six weeks under the hot summer sun to achieve optimum results. If your soil is too hard or too sandy, this may be remedied by adding organic materials like compost, manure or shredded wood products. A little research on the subject will go a long way.

Last but not least, if you find you’re still having a problem with a particular plant, try a disease-resistant variety instead. No better solution than avoiding the possibility altogether!

Good luck and great gardening!

More: Next week, we create ambiance in the garden.

Dianne Venetta

Dianne is an author, entrepreneur, and mother. She writes the blog BloominThyme and volunteers as garden coordinator for her children's school garden. At the end of the day, if she can inspire someone to stop and smell the roses (or rosemary), kiss their child and husband goodnight, be kind to a neighbor and Mother Earth, then she's done all right.

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  • Sales

     Hi,
    I have these things on my plants in my hydroponic. I don’t know if I can use these things to control them. So I decided to ask. Is it possible for me to use these kitchen solutions in my hydroponics or not?
    Thank you!

  • Anonymous

    There are quite a lot of advantages of hydroponic gardening that is much better than the soil based gardening. If the growth rate of plants with normal gardening and hydroponic gardening, under same conditions are compared, then it will be found that a hydroponic plant grows 30-50 percent faster than a plant grown on soil. 

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