Nothing you can buy in a store is natural. You can get things that will deter/kill insects that aren't toxic to humans, like peppermint extract, but I don't think calling something that humans pressed and processed from a plant that was grown, cultivated, and bred by humans "natural" makes any sense. Most plants produce their own insecticides, so make a list of your favorite herb/flower scents, check which ones work/are available, and go to town.

Remove the food source and the spiders will go. They frequent certain places because the hunting is good.

Lavender oil, (and a little tea tree if ur feeling fancy) drop some oil in a spray bottle with water. I love the shit so I dump the oil in there but a table spoon will do. Also useful for ticks on hikes around your ankles. Note some species dgaf.