Sounds like you need to create some artificial shade with a pergola, lath house or similar structure. I made a fairly inexpensive pergola using split rails (like in the fences) as uprights - they have a nice natural feel. The top could be shade cloth, lattice or even braches from your dying trees.

Also make sure the garden is well mulched and supplied with lots of organic matter. Don't use any chemical fertilizers, they encouage unsustainable growth. And keep ahead of the watering if we have another dry year. Lots of shade plants will tolerate sun if the soil is good and kept moist.

Ted

You might also be able to plant some fast growing tall annuals for quick shade.

Patio umbrellas could work, but I suppose that could be expensive for a large area unless you could find some at garage sales.

Annuals. I am thinking the smaller flowered ornamental sunflowers and Castor bean. If you put up some kind of support, pole beans would be easy, and you could train smaller leaved squashes (like sphagetti squash) or muskmelons.

Another possiblity - you probably have lots of gardening friends who understand completely.

I was a plant-sitter for 2 summers for a friend whose husband had already used a front end loader to destroy more than half of her iris and hosta and daylilies. I was happy to do it. There was history and memories involved with many of those plants, so she sought refuge for what was left with friends who garden. I am sure your friends can find a few corners where they can slip in some plants until you are in a position to take them back. Carmellia

Google shade sails!