How to increase the soil acidity for established tomato plants naturally? I'm not getting many blooms or viable tomatoes for this late in the season.
There are a few things you can do. Here is a link to preparing your soil and growing specifics - www.thespruce.com/
Some plants prefer a soil pH on the more acidic end of the spectrum. There are additives that can be used to increase the acidity of your garden soil. This is a page about making soil acidic for tomato plants.
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The pH of soil affects the ability of plants to take up nutrients in the soil through their roots. If the soil is too acidic or too alkaline (basic) important nutrients like nitrogen, potassium, and phosphorus become less available to your plants.