Q: I have had problems with my tomato plants in the last few years. They begin to lose leaves from the ground up and soon, all that’s left is tufts of leaves on the ends of the branches. The leaves get little brown spots and then turn all brown. I was told that this had to do with not enough fertilizer or poisoned soil or some kind of blight. Nothing I have tried works. What is this and can it be fixed?
A: There is a solution but, unfortunately, Your problem with the tomatoes is not rare or unfixable.
A fungal disease called septoria leaf spot is your culprit. But, and this is a big but, it cannot be cured once it starts. It can only be prevented.
This is basically the same story for all tomato fungal diseases. If you wait for the disease to start, it’s difficult to know how much more of the plant is infected. So, start before you see any spots or rots. Septoria can first be seen in early July. It happens to plants that are stressed and the work of producing flowers and fruit is stressful. You want to use a fungicide containing chlorothalonil. It can be found in the brands of Daconil and Fungonil. It’s a concentrate that is mixed in water and applied with a pressurized sprayer.
Timing is critical when protecting plants. Begin spraying at the end of June or the very beginning of July. You will be protecting the plants, not curing them. Label directions will tell you to repeat applications at seven to 10-day intervals. But here’s an important fact that new gardeners don’t think about. This fungicide is water soluble and if it rains or you overhead water, your protection gets washed away. If the hose is placed on the ground and water is applied there, your invisible raincoat remains.
There is also an organic alternative called Serenade but there appears to be debate among gardeners on how effective it is. Septoria starts on the lowest leaves of the plant with small brown spots on the leaves. The leaves turn yellow, then brown, dry up and fall off. It works its way up the plant. Every diseased leaf that falls and ends up in the soil is what starts septoria next year.
Septoria only affects the leaves; fruit is unmarked. But a plant with little or no leaves will not make fruit. Mix your fungicide fresh each time you spray. The mix does not hold in your sprayer so use it up in one application.
Q: Why are there little apples falling off my apple trees? I am finding really small apples on the ground and they look perfect. What’s gone wrong?
A: It’s just Mother Nature dumping her duds. When the tree was flowering, a bee or other pollinator stopped by to swap pollen between your apple blossoms and another apple or possibly a crabapple. But bees did not necessarily get every flower.
The apple tree’s great purpose in the cosmos is to make seeds, not give you eating material. By the middle of June to early July, all the fruit grew, whether it was pollinated or not. At this time, the tree becomes aware of the nonseed producers or the duds. And these are dumped unceremoniously off the tree.
It has happened every year since there have been apple trees on the planet. It even has its own descriptive name: June drop. You can also lose apples if the flowers got lightly frosted and could not be pollinated. Or if you only have one apple tree or several of the same kind of apple tree, there is no different apple pollen to mix and match. This is not a singular phenomenon of apples. It happens to other fruit and nut trees. There is no reason for concern and there’s nothing you can do about this if you have more than one variety planted. And in today’s weird world, there are so many other more worthy things to worry about.
Questions? Call the MSU Extension Master Gardener hot line at 888-678-3464. Gretchen Voyle is an MSU extension horticulture educator, retired.
