Since COVID 19 has happened is it safe to use Bat Poo in my vegetable garden? I live in Ontario, Canada, and have a bat house full of last count 23 bats with lots of poo.
It's certainly worth investigating and I'm not sure there is an answer yet, since we're still in the throes of COVID. I want to refer you to the Bat Conservation International organization; I suggest you contact them and find out if they are still recommending bat guano as fertilizer. Here is the URL: https://www.batcon.org/article/guano-bats-gift-to-gardeners/
You may also want to contact your university extension service with this question: https://www.gardeningknowhow.com/extension-search
I’m worried about pests and getting sea grasses eyc
Sand and pests wouldn't be the problem as much as excessive salt or compacting the soil. You probably didn't have enough sand to pose a problem, though.
I have a burn pile we use to burn yard waste, tree limbs, weeds, etc. After several years it has mounded up and I was wanting to know if these ashes could be used in a garden or in the yard?
I would compost them, first. This will prevent pH swings, and burns.
https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/using-wood-ashes.htm
https://www.gardeningknowhow.com/composting/ingredients/composting-ashes.htm
Are they suitable for all houseplants?
They are most often used to root plants or to grow succulents or plants that need a very well-draining soil.
https://www.gardeningknowhow.com/garden-how-to/propagation/propgen/what-is-semi-hydroponics.htm
What is a safe ratio for a soluble spray solution of potassiun/water
I didn't find a calculation but this info about potassium may help:
https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/plants-potassium.htm
https://www.canr.msu.edu/field_crops/uploads/archive/E0896.pdf
The soil in my location if clay based and I have read that adding iron to the soil will improve growing conditions. What is the best way to add iron to the soil?
Actually, clay soil will contain quite a bit of iron, already! Amending clay soils should be done with soft organic material, such as perlite, vermiculite, coco-coir, peat-moss, or other materials to break up the clay content. By far, the best way to amend the soil will be compost. Well composted organic material will break up the stickiness of the soil, while adding all of the nutrients that will be missing.
https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/how-to-improve-clay-soil.htm
ground is very hard and during dryt seasons the ground cracks open
Sure! We have just the articles to help you:
https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/how-to-improve-clay-soil.htm
https://www.gardeningknowhow.com/special/organic/how-to-easily-improve-your-clay-soil.htm
https://www.gardeningknowhow.com/edible/grains/cover-crops/cover-crops-for-clay-soil.htm