I'm trying to enhance the soil without using chemical fertilizers.
You will need to compost them before hand. You will also want to avoid anything that comes from meat or dairy in your compost.
These articles will help: https://www.gardeningknowhow.com/composting/ingredients/composting-kitchen-scraps.htm
https://www.gardeningknowhow.com/composting/basics/ultimate-beginners-guide-composting.htm
Do they need a rich well composted soil ?
Yes. Unless your soil is already loose and fertile, add a lot of organic matter like compost or well-aged manure.
This article tells how:
https://www.gardeningknowhow.com/edible/herbs/garlic/growing-garlic.htm
Last fall I planted garlic in my 8500' high mountain valley garden for the first time. In early August I was unexpectedly called away from home to help my son and his family. It is now Oct. 7th and I have just returned home. Though neighbors helped out by watering my garden during a very dry fall here in the mountains of Colorado, they did not attempt to harvest my crop of garlic. They stopped watering the garlic over three weeks ago and there have been fairly steady nights of freezing. My garlic plants have entirely brown and dried out leaves. I dug up a few bulbs and they look healthy but moist with no leaves staying attached. I want to dry it as best as possible but I'm unclear of how best to save my several dozen bulbs. Please advise.
If they look good, then they will be fine to save. These articles will help you to harvest garlic: https://www.gardeningknowhow.com/edible/herbs/garlic/save-garlic-next-year.htm
https://www.gardeningknowhow.com/edible/herbs/garlic/how-to-store-garlic.htm
I am an organic gardener and wish to plant onion sets and garlic this year. Can you plant in November or should I wait until February? Can you also tell me about adding blood and bone meal to the soil prior to or throughout the growing season? Their are many supplemental fertilizers that can be added without the generic 10-10-10 or 6-6-6 application. Thanks Ron
These three articles are all about growing garlic and onions in your zone:
https://www.gardeningknowhow.com/garden-how-to/gardening-by-zone/zone-9-10-11/zone-9-onions.htm
https://www.gardeningknowhow.com/edible/herbs/garlic/how-to-grow-garlic-in-warmer-climates.htm
https://www.gardeningknowhow.com/edible/herbs/garlic/feeding-garlic-plants.htm
Our experts say to plant warm-climate garlic in late October through early December. Depending upon the strain of onions you choose, there may be different planting requirements. Our suggestion is to check with your local extension office to find out about best practices for growing both in your specific area.
the small bugs have a hard outer shell and seem to feed on part of the garlic cloves. Are they some type of nematods in the soil? How can I get rid of them
Unfortunately, your photo did not come through, so I cannot see the pest in question.
There are many organic solutions that will not bother your plants, and will help to get rid of most insects in the area.
These articles will help: https://www.gardeningknowhow.com/special/organic/what-are-organic-pesticides.htm
https://www.gardeningknowhow.com/edible/herbs/garlic/growing-garlic.htm
Im going to plant Casava and Im thinking in between to plant Garlic Will it be good for the Casava or Hurt it
I cannot find any literature to suggest that they would have any negative interaction. It would not hurt to try, as long as you give enough room between plants for them to be happy.
Here are a couple of articles that will help you to care for each plant: https://www.gardeningknowhow.com/edible/vegetables/cassava/growing-cassava-yuca.htm
https://www.gardeningknowhow.com/edible/herbs/garlic/growing-garlic.htm
I live in the South Island of New Zealand where we experience frequent droughts during spring and sometimes summer periods, but irrigation is available.
You will need to test your soil to find out what it needs.
These articles will help:
https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/soil-ph-plants.htm
https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/soil-ph-plants.htm
https://www.gardeningknowhow.com/special/organic/the-importance-of-soil-for-an-organic-garden.htm