Generally trees and shrubs are the backbone of a garden design, with
help from hardscape (paths, patios) and features like benches, statues,
fountains. Then perennials and annuals round out the design.
In a 5b climate, you've got lots of choices for plant materials.
The first thing to do is identify a style that you like. Your
proposed island beds sound rather municipal park to me.... like you haven't
thought about variations in height and texture adding to the landscape.
Another thing to think about is changes with the seasons... for instance,
spring bulbs are pretty well gone by early summer, which is about when the
roses kick in. For a lot of people, summer annuals carry most of the
color, until fall when chrysanthemums and colored leaves pick up the load.
Changes in dominant colors also tend to go with the seasons ; natural
prairies tend to have a lot of pink in the spring, violets and blues in the
summer, and yellows and oranges in the fall, for instance.
I'd suggest you want to do a couple of things now: 1) take some photos
of the house and yard, particularly from your main entrance or main
view into the property, and the view from the back door or whatever
your entrance into the private areas of your yard might be. 2)
Think about how you want to use your area -- you've got retaining walls,
do you have an area where you'd like to sit and read a book or bbq in
peace and quiet? If you want a bird bath, is it near a water source, and
are there shrubs or other good cover for the birds? Will you have a feeder?
Do you like lawn? If so, you're going to want to work on layouts that will
give a semi-sane mowing path (nothing like having to lift and carry
a nice heavy lawnmower through a patch of shrubbery to mow an isolated
stretch of lawn!). Do you have some spots to sit and talk with friends
Head for the library and check out the books on garden design, landscaping,
and if you're not an enthusiastic gardener, native plants, particularly
0native trees and shrubs. Identify styles that appeal to you -- for instance,
I prefer the informal or natural styles, and start getting hives when
I think about having to trim and weed a knot garden. <g> I grew up
with prairie, so I think a large green monoculture lawn is deadly dull,
while my husband likes the effect... so we've got lawn in front, where
he's likely to spend time, and wilder stuff in back, for me. <g>
Then start sketching over your photos... as you do so, think about
putting high maintenance plants near your watering sources (if you
will have to water), lower maintenance things back where the hose won't
reach easily. Think about shade and sun, and grouping plants of similar
culture together. Do you need a play area for kids and/or dogs?
This is a good winter project. Next spring, you can lay out any beds, etc,
with flour or garden hose and begin to revise your plans.
For most of us, garden design is not an easy thing, or something that
comes with a set of plans, unless you've hired a landscape architect.
Most gardens wind up evolving over a period of time, as you decide
this plant looks better over there, and what was I thinking planting
so close to the house that the shrubs are poking through the kitchen
window and.... and gee, those daylilies need more light than they're
getting now that the apple tree is taller...