Answer: I think redoing an entire landscape is a huge undertaking, but it you work at it a section at a time, you should be rewarded with an outstanding new yard. You can renovate a lawn by using a vegetation killer, then rototilling, adding organic amendments, then leveling and broadcasting seed. This is best done in the fall when temperatures are cool and rainfall abundant. Once you've killed the weeds and grass, you shouldn't have problems with insects (they'll go where the grass is greener and they can find other insects to eat.)
Right now I think I'd concentrate on the flower beds. Dig out the weeds first, then lay a 4-5" layer of compost over the top of the bed and dig it in to a depth of 8-10". Level the area and plant your annuals and perennials, then cover the bare earth with weed barrier and top it off with a decorative mulch such as bark or rocks. This will keep the area virtually weed-free for a very long time. Perennials popular in your growing region include the dozens that are listed on the following website:
When you click on a plant name, you'll see a photo, a complete description, and growing requirements. Make your plant choices to correspond with whether the planting site is sunny or shady.
Best wishes with your new landscape!
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