There may not be a one size fits all regimen, but there IS a one size fits 99.9% regimen which has proven to bear fruit for a LOT of growers. I probably have about 300 plants covering at least 200 species and I don't know how many genera - maybe 125 to150. All those plants are treated exactly the same, except for allowances that a little more than half of them snooze the winter away, dormant, in a cold garage where they need no care other than the snow I toss on top of them occasionally through the winter so roots don't dry out. The houseplants and succulents grow under the same lights, get watered ON A SCHEDULE at the same time, get fertilized with the same fertilizer, and manage to remain in excellent health, year after year. It's true that when all you have is natural light, plants will need to be sited in consideration of their light preferences, and temperatures are a consideration, but the portion of the cultural conditions that are provided by the grower that are most apt to spawn trouble will relate to a triangle formed by soil choice, watering habits, and proper nutrition. These three factors are so intimately related that it's difficult to discuss one without including the others unless you're growing in a soil that allows you to water correctly. The idea that different plants require different treatment (other than light and temps) comes largely from the fact that some plants are better able to tolerate adversity. 'Tolerate' somehow translated to 'appreciate', and soon people were believing some plants LIKED soils wetter than other plants. Most of the plants you'll grow perform best when their soils are barely damp - not wet, and never soggy. If you're interested, read the link I left below. It will help you avoid most of the frustration suffered by people new to the growing experience if you put it to practical use. Al Here is a link that might be useful: More here

I wouldn't plant right up against them. I'd spread out a layer of mulch (we use pine straw but shredded hardwood is very nice) in a circle 5-6 feet all the way around the tree. Or certainly if you can get a nice carpet of moss going, that would serve a similar purpose. Then plant further out. I think planting too close is hard on the plants, hard for you to dig and to maintain (lots of root competition), and potentially stressful for the tree (depending on how much you do). A nice layer of mulch or moss is plenty attractive and restful to the eye. If you have any deer nearby, don't bother planting hostas. Getting fern divisions from your mom sounds like a good way to start (and economical). If you want to id them (the ferns), take a picture and post it on the Name that Plant forum.

The advantages of planting most perennials, shrubs, and trees (in our zone) in early to mid fall is slight compared to planting them in early to mid spring. In colder climates, it's often best to wait until spring to plant. If you are planting a fast growing or top-heavy deciduous tree or shrub, fall might give the roots time to get more well established before the plant experiences wind that could push the tree, with a smaller root ball, over. Basically, plant at whichever time is more convient to YOU. If you plant them correctly and water them until they get established either time (in this climate zone) would work just great.

Much of California is hotter than Hell (100s F.) in summer east of the outermost coastal fringe*, hence the chronic problem with dangerous fires. With a number of the native species - including various ceanothus - growing only close to the ocean in nature. Even a lot of the redwood area has a hot summer, with fog drip being a large part of what makes it possible for these giant trees to live there. *Death Valley is located in California