I've done several discrete grows in the backyard. From my experience, it isn't that important that you carefully select plant materials that match or mimic cannabis, only that you have a tremendous amount of stuff planted. While Japanese Maple looks very similar it is a perennial that can be very pricey. Some "lace leaf" types (even small ones) can run a few hundred dollars depending on their degree of serration in the leaves, rarity etc. A wide variety of plants in a relatively small area can overwhelm and distract the viewer. This is a old trick used in landscaping. Confuse and/or re-direct with sheer volume. Using annuals that have showy, large blooms such as impatiens, daisies, lantana and a ton of other plants can re-direct the eye to a portion of the garden that you might prefer others not notice. Go to a garden center and look around, ask questions. You might discover some plants are almost as much fun to grow as your precious girls.