Large yards in Arizona require careful consideration for landscape design. Keep your landscape affordable by searching for reasonable prices on materials before purchase. Designate specific uses for areas of the yard, and borrow friends and family members to help with manual labor to save on manpower costs.
Design any green spaces of your yard by grouping plants with like water needs in individual beds. Native flowers, trees, shrubs and vines will help keep your water budget in check. Choose plants known to perform well in your specific region of Arizona. Keep your plant budget down by purchasing plants from community native plant sales, growers or surplus dealers that sell plants left over from large commercial landscape design jobs. Select healthy plants that you won't need to supplement with minerals or fertilizers.
If you need an area of turf, keep the long-term cost in mind. Purchase water-wise turf such as Bermuda, known to perform well in the area with minimal care. In the colder areas of Arizona, Bermuda is dormant in winter, needing little care and no irrigation. In lieu of grass, consider purchasing used artificial turf. It's evergreen and needs little care. Check with landscape suppliers and purchase discontinued styles or leftover pieces appropriate for the space.
Since your yard is large, you'll find ample areas left blank after you've planted gardens and small spaces of turf. These areas can be covered by reasonably priced crushed landscape rock or another surface materials suitable for walking paths. Purchasing these materials in bulk from quarries is typically cheaper than purchasing small amounts from home and garden stores. Choose a material that won't track dirt into your home or blow away with the winter winds.
Get stingy with your garden dollars. Water plants using recycled rainwater collected in rain barrels. Purchase used outdoor furniture from overstock or recycled building supply stores and spruce it up yourself. Ask friends to give you seed from flowers or segments of divided perennials to enhance your garden without cost. Select plants that are disease and pest resistant so you don't have to purchase products to care for them. Learn as much as you can about frugal gardening by attending free or low-cost landscape classes offered at local garden centers or cooperative extensions in your area.