“Which is the natural and most efficient solution against pests, aphids, white powder, etc. that year after year destroy our vegetables?” Question from Doina of Bothell, Washington
Answer: I wish that I could give you a simple answer. There are so many vegetables and so many pests and diseases that attack them that it is impossible to know where to start. You specifically mention aphids and powdery mildew, so I will give you guidelines for managing these. It will be followed up by two general steps that you can take to discourage veggie pests and diseases.
Aphids are slow-moving insects that suck the juices out of tender plant parts, like stem tips and leaves. When aphid populations are high, they cover the tips of growing plants in masses. It looks creepy and can seem overwhelming. Lucky for you, they are easy to manage organically.
I always start by putting my hose setting on jet or center, then I spray. Aphids are delicate and can be spritzed off a plant in no time. To keep them from returning, follow up by spraying your plants with an insecticidal soap that is OMRI Listed for organic gardening. Keep them spritzed as you see more aphids. This method will put them in check quickly.
Powdery Mildew Management
This one is really simple! Powdery mildew is a leaf surface mold that can be removed with all-natural products containing the mild chemical potassium bicarbonate, which is similar to baking soda. GreenCure® is one of the most popular commercial examples on the market. Just spray your mildew-ridden squash or cucumber leaves with these products and the spots disappear. It’s a remarkable transformation.
Two Steps For Disease- and Pest-Free Vegetables
Here are two more steps towards protecting your plants from pests and diseases. Both may sound deceivingly obvious.
1. Don’t stress your vegetables. When plants become stressed, they create stress chemicals that are detected by insect pests that are then attracted to the plants. What’s worst is that many common pests, like cucumber beetles and leafhoppers, spread common vegetable diseases. Stress also makes plants far more susceptible to disease. Weak plants have weakened immunity. So, grow your plants in well-fortified soil (see our long list of Black Gold soil amendments), provide them with good fertilizer throughout the season, and keep them well watered.
2. Choose resistant vegetable varieties (!!!). Choosing good varieties is the single most important way to protect your crops. When selecting varieties to grow in your garden, look for descriptions of pest and disease resistance. Award-winning plants also tend to be resistant and robust. Plants bred for resistance are the easiest to care for naturally and organically.
I also suggest you read the Fafard (our sister brand) article, Beating Vegetable Garden Pests Naturally, as well. It has even more information to help you. I hope that these tips help!
Black Gold Horticulturist