Start reading about tomato pests and diseases and you begin to wonder how any tomato ever makes it at all. After weeks of episodic rain my tomato plants are growing like kudzu, but I noticed something this morning that sent me looking for fungicide recipes: yellowing around large brown spots on the lower leaves of one of the plants. I am not happy about this.
Early Blight is a fungal disease that is easily transmitted from infected soil, tools, some insects, (ex. aphids), or any type of physical contact. It can live up to two years. Wet seasons like the one we’ve been having provide ideal conditions for it to survive and thrive. The lower leaves are affected first, yellowing and falling off.
Some of the most effective controls are:
- Removing the lower leaves, especially those which contact the ground
- Mulching to reduce splattering of the fungal spores up to the leaves
- Watering the soil, not the plant, to keep the plant dry and inhospitable to fungus growth
- Spraying with copper or sulfur–use caution, too much copper can harm earthworms
- Serenade Disease Control has gotten some good buzz. It’s listed as approved by OMRI (Organic Materials Review Institute)
- Neem oil, especially as a preventative before the blight appears
I removed the lower, affected leaves, added some fresh mulch, and sprayed with a baking soda solution (1 T. baking soda, 1 T. oil, squirt of liquid soap/1 gallon of water). Of course, 30 minutes later it rained again, so I’m anticipating a battle with this. For the benefit of the plants yet to show signs, I am going to hit them with neem oil. I’ve heard a milk solution (1 part milk to 9 parts water) is also helpful so I may try that, too– if it ever quits raining! Remind me how I wouldn’t quit whining about the nonstop rain when the next drought hits . . .
This is an article about pruning the lower parts of the tomato plant for this reason.
And this is a discussion about Early Blight on GardenWeb, one of my favorite resources.
T.L.
How did the blight fight turn out last year? Anything you would do differently/the same this year? I’m wanting to protect my plants before the blight hits this season, but don’t have neem oil (don’t know where to even find it locally). I was thinking about using your above recipes – did they work well? Thanks!!
Kalinda–It never got bad, fortunately. Of course it’s hard to know what you did to help when you try multiple methods, but I think keeping the leaves off the ground, good air circulation, and mulching helps. I have found neem oil at Lowe’s, although I can’t say if they carry it in all their stores. I never tried the milk solution, but I believe in starting as minimal as possible, so that or the baking soda will be my first lines of defense this year. Good luck.
I’ve had good success controlling ‘powdery mildew’ off courgettes, using Neem + Baking soda + SprayFix/RainGard as spreader sticker to keep the solution on.
Now I’m having to look into what to use, on my tomatoes..
Neem oil, or neem leaf powder (soak it in water, strain thru a cloth) are available at most Indian wholesalers. Leaf powder is anti-fungal but only the oil is anti-insect as well. My recipe (mildew) is 1 tsp (5 ml) baking soda, 1-2 tsp neem oil and/or water from soaking neem leaf powder, 1 ml RainGard per liter. Normally I make about 4.5 liters.
Plus, about 5 ml of detergent overall if I’m using neem oil, to emulsify — if powder, I probably use 5-8 grams total. Pressure sprayer with wand, very helpful.
Now to see how this works on tomatoes!
I know this is an old post but I’m wondering if you used your mix again with success? Was it 1T Neem oil or did you use another oil? Thanks!