Established

GENERAL:

Every tree is an individual, with its own unique environmental, soil and underground conditions. Even a few feet can make a substantial difference in overall requirements. Some adjustment of these guidelines may be necessary for each tree.

If proper watering is performed in the first year (see our 1st year tree watering instructions), the tree should be well established and able to thrive mostly on its own going forward. However, severe weather conditions can cause health stress for trees just as it does people. If a tree already has challenges, whether natural or human-inflicted, sometimes supplemental watering during a critical week can mean the difference between life or death. Proper supplemental watering is also important when attempting to revitalize a stressed or dying tree.

All trees, regardless of age or size, should be given supplemental water during unusually hot and/or dry stretches of weather at any time of year, but MOST IMPORTANTLY during the hottest months of June, July and August.

GENERAL WATERING PATTERN:

Tree root zones should get a deep soaking (up to 18” depth ideally), then be allowed to dry out. DRYING OUT IS IMPORTANT. If the roots stay constantly wet, they will rot and the tree will die.

WHEN TO:

Late evenings or early mornings are the best time to water trees and plants.

October – March:

Water only if there is an unusual period of drought (a week or more without rain), and no soaking rain is imminent.

April – September*:

Evaluate your watering needs when the temperature reaches 90 degrees F or higher for 2 or more days in a row, with no recent soaking rain and none is imminent.

*June – August:

These are critical months to monitor the weather. If outside conditions are stressful for humans, they are stressful for trees.

HOW MUCH:

The goal is to soak the ground up to roughly 18” depth, in a “donut” shape around the tree, roughly underneath the outer 1/2 of the tree canopy. Watering any closer to the trunk is not as effective for an established tree.

HOW TO:

• Use a hose without a nozzle laid down anywhere in this “donut” zone. Allow it to run for 30 seconds, a minute, or more in each spot to achieve a good soaking, to approximately 18”. If you have no idea, just do the best you can, some water is better than none. However, note the necessity to let the ground dry out between waterings. Do not leave the hose to run in one spot for more than about 5 minutes. Most of the time, 1-2 minutes is enough to achieve a good soaking given the average level of run-off.
• Soaker hoses can also be used, placed around the tree in the donut zone (NOT near or against the trunk), and left on perhaps overnight for a thorough soaking, but don't forget to turn it off!

INDIVIDUAL CONSIDERATIONS:

Sun exposure. What is the tree's sun exposure? If the tree is situated mostly in the shade, less watering may be required. If in full sun, more may be required.

Drainage. Poor drainage can also affect the timing and amounts of supplemental water needed.

Slopes. Slopes can cause water to run off before soaking into the ground. This
should be accounted for in watering.

MULCH:

If you use mulch, which can benefit trees only IF applied properly, we recommend using only coarse hardwood chips or pine bark (for evergreens) of roughly 1-2” diameter. No more than a single layer of 1-2” depth is necessary, more than this could be harmful as it does not mimic a tree's natural environment. We recommend NOT using shredded mulch, as this is often applied too deep, and can abruptly cut off the natural exchange of water and oxygen between the air and soil, which tree roots depend heavily on. In addition, shredded mulch over time will develop a glazed-over surface, which
causes much of the rain water to run off, and not make it into the soil for the tree roots. In addition to that, shredded mulch will soak up much of the water that is meant for the tree roots. If you do use apply shredded mulch, keep only a light layer of less that 1 inch, and break up the surface occasionally.

DO NOTS:

DO NOT OVERWATER. This is worse for your new tree than no supplemental watering at all. If the roots stay constantly wet, they will rot and the tree will die.

DO NOT USE A SPRINKLER TO WATER TREES. 2 problems with this. The water is spread too thin, and is likely not to soak deep enough into the ground to reach all of the absorbing roots.

This method also sprays water onto the tree trunk, which is not natural (does not mimic the tree's natural environment), and can lead to trunk decay and circulatory problems.

DO NOT WATER THE TREE TRUNK. Water should be applied primarily underneath the outer half of the limbs for an established tree – this is where the majority of the absorbing roots will be.

DO NOT PILE MULCH, DIRT OR ANY LOOSE DEBRIS AGAINST THE TREE TRUNK. The trunk is designed to be exposed to air and sunlight, down to where it flares outward at the base and transitions to roots. You should be able to see this root flare at the base of any tree, whether new or established.

DO NOT MAKE SUDDEN CHANGES. Any sudden change in the tree's environment, whether above or below ground, is likely to adversely affect its health, just as it would for any other living being. Over-mulching is the most common mistake we see in tree care – this will suddenly cut off the natural oxygen/water exchange between the air and soil.

DO NOT “EDGE” WITHIN THE TREE'S ROOT ZONE. Tree roots grow wide and shallow, and the root tips grow upward into the top few inches of soil so they can “breathe” oxygen in the soil pore spaces. You don't see them, they are tiny, but they are crucial for absorbing water and nutrients. Edging with shovels around trees severs these root tips, interrupting absorption and causing the tree to have to regenerate them, using up valuable resources to do so. Dead or dying limbs may also appear in the canopy as a result. General rule of thumb: If it does not occur in nature, it is probably not going to be good for the tree