Definitely planning to keep things as organic as possible, but willing to spray for fungal issues if needed. Thanks for the suggestions!
Thanks for the reply!
I’m definitely aware that Seattle isn’t an ideal climate for avocados. However, many non-commercial varieties of Mexican-race avocados do well in the Mexican highlands and areas along the Oregon/northern CA coast that have similar summer heat to Seattle. I’m putting my mother trees in a greenhouse and planning to cross-breed all the hardiest varieties available in search of seedlings that can survive here. I’m not expecting high or even moderate success rates, and would accept total failure, so it’s more like a mini-experimental research station. The coldest temperature in the 4 years I’ve lived here was ~23° and I’ve never seen the ground freeze solid, so I’m cautiously optimistic that Seattle is warming quickly enough compared to many other locations that over the coming decades it will slowly become more conducive to some of this stuff. Here’s my thread for the avocado stuff:
As for the soil, there’s a layer of true topsoil but below that it’s medium-hard hardpan (more like slightly compressed clay/sand mixture that is easily broken with a shovel) ~2 feet below the surface in the back yard and ~3-4 feet below the surface in the front yard. There’s a layer of pure glacial clay about 5-6 ft below ground level in the back yard, but I haven’t dug that deep in the front yet to see what it’s like. The front yard is about 6 or 7 feet higher than the back yard, so not sure if that’s just thicker topsoil or if the clay also slopes up.