Q.tomato plant trimming
My tomato plants are, I fear, way too big and overgrown, and are suffocating my other plants from the sun. Can I trim them without harming them?
Also, I heard marigolds affect them, but I forgot how except that the effect was positive, so I did so. How does it affect them?
Here is a link that will help you.
Marigolds can help deter pests in the garden! I plant them at the edges of all my raised beds, and they look pretty too!
You can prune them if you wish...or not :-). If you think your other plants aren't getting enough sun, go ahead & take the tomato plants down a bit. This article will give you some tips on how to prune tomatoes the right way: https://www.gardeningknowhow.com/edible/vegetables/tomato/should-you-prune-tomato-plants.htm
and this article describes "sucker" stems. You can thin your plants out by pinching these off too. https://www.gardeningknowhow.com/edible/vegetables/tomato/tomato-plant-suckers.htm