Too Much Water
If trees are watered too much, its soil becomes over-saturated and the roots suffocate and die. And stagnant wet soil attracts unwanted root rot organisms that can also kill trees. Certain tree species can handle wet soil conditions (River Birch, Cypress, Sycamore, Etc.), but most cannot. You want to water enough to moisten the soil, but not overly-saturate it. Signs that your tree is being over-watered include yellow leaves, brittle leaves, visible fungus or algae growth on the soil beneath the tree, black tree roots (root rot), and more.
Not Enough Water
Trees need water for sustenance and growth, and even more-so during drought seasons or periods with extended lack of precipitation. Without water, trees cannot survive. It is that simple. It is important to find a happy-medium between too much and not enough water when it comes to your trees. During growing season, trees should be watered once a week, more or less depending on the amount of rain at the time. You want to water them, allow the water to soak in, and wait a few days before re-watering. If the soil around the tree is still moist one inch in, it does not need to be watered just yet. If it is dry 1 inch into the soil, it is ready for more water.
The Right Amount of Water
The trick to knowing how much water to give your tree starts with the tree trunk’s diameter. Measure this in inches, and then multiply that times five. Trees should get five gallons of water per inch of their trunk’s diameter, over an extended period of time. This is why line drips, bubbler heads, and irrigation systems come so highly recommended. You don’t want to dump 20 gallons of water at the base of a tree. That can over-saturate and harm the tree. If you only have a garden hose, simply turn the water on slow and low and then place it at the base of the tree for a few hours.
Additional Tree Watering Tips:
• Water At Night When Evaporation Levels are Lower
• Do Not Use Spray-Head Sprinklers – They are Less Efficient
• Lay Mulch at the Base of Trees to Conserve Moisture
• Combat Weeds and Other Nuisances that Compete with a Tree’s Water Source
• Control Water Run-Off by Edging the Mulch or Soil Around the Base of the Tree