Neglect followed by overwatering is a big problem for plants this time of year. When plants are neglected the whole plant becomes stressed including the roots. Most people will try to salvage a crisped or withering plant by drowning it with water, and that is literally what they are doing. Roots do need water but they also need oxygen. Too much water and the roots will suffocate. The best way to rescue plants is by giving them some shade, even if they are sun loving plants. Water just enough to allow the roots to get a drink and then drain, wait patiently for new growth, then move the plant or remove the shade to allow for its sunlight requirements.
A bit more about roots and water. Roots will only grow as deep as the watering goes. If your water is only getting 2 inches below the surface then that’s where the roots will want to stay. Watering deep will allow for roots to stretch down and establish a strong healthy system. This goes for lawns, trees and shrubs too.
Watering deep means watering smart. The best time of day to water is in the morning. Cool morning temps allows for up to 50% more water retention then watering mid day. This allows for water to travel deeper into the soil. A summer mid day watering means that extra 50% is going into the air. Water is lost through wind, and quick evaporation from soil. Plants also like to take a little siesta of sorts. In the high temps, the pores sort of close up shop, and their cell activity slows down to retain their strength. So they are less likely to draw up that afternoon water. Watering at night is also an option. However, this allows plant foliage to stay wet all night with mild temperatures, which promotes fungus and disease.
A few more tips: Drip lines and or a soaker hose placed under mulch are two of the best ways to conserve water. If you are watering with a hose, please take a moment to make sure the water is running cool. Water from a hose that has been sitting in the sun can get over 100 degrees. Water based on the weather; if there is a week of cool temps cut back on watering, if its 90+ consider watering daily.