Because I value potable water, I prioritize its use. Edibles and newly planted shrubs and trees, which are highly vulnerable to drought stress, earn the right to receive water from my spigot. When plants become established, meaning that they’ve regenerated enough roots to sustain themselves without supplemental irrigation, they’re only watered when the need arises.
After experiencing decades of dry, torrid summers, I know that even established shrubs and trees may succumb to hot, dry summers, which means that you need to visit your landscape often and be on the lookout for the initial signs of water stress: curling or crinkling leaves, yellowing or off-colored, dull-looking leaves, and brown or scorched areas along the leaf margins. Obviously, when you see azalea leaves that look like brown potato chips or Florida anise leaves that look like wilted leaf lettuce, the damage is already done. More severe signs of water stress include leaf drop and branch dieback. These aboveground signs are only a reflection of the unseen damage belowground, particularly to the fine, water- and mineral-absorbing roots.
One tree that has thrived for the past decade without any supplemental irrigation is an Italian stone pine (Pinus pinea). I purchased it in a one-gallon decorative pot right after the Christmas holiday season. This Colorado blue spruce lookalike was on the discounted table, surrounded by poinsettias and rosemaries sheared into miniature Christmas trees. It survived bitterly cold winters without a scratch when temperatures dropped to single digits. This Mediterranean native is now 12 feet high and 6 feet wide. It morphed from the cute, short-needled blue conifer into a shaggy-looking green-needled attention-getting specimen.
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