(Continued from Planting 6: Staking)
It is easy to think, once our new tree is back in the earth, that all is well and that Nature can take care of herself. Not so. The new tree’s water requirements are the same as when it was in the pot or basket—perhaps much more, if planted in a bright, sunny location. (Where else?)
And remember, the new root growth we are counting on will take some time, multiple seasons. This is not an overnight change. Freshly planted in a perfect site that we made for it, the new tree will be just as unhappy after three days without water as it would be if it were still in its pot.
My favourite method of ensuring that new plantings get the water they need is to build a small earth dam, a berm, some say a dike, all around the edge of the planting hole. Size should be consistent with planting site size—generally four to five inches of packed soil which, in cross-section, would resemble a bell, and will hold a couple of inches of water easily. Fill up the berm with two inches of water. I do this by pointing the hose at the trunk, so as not to cause any erosion of the planting site or berm.
Did the water just sit there or did it soak in right away? If it sat, it won’t stay for too long, and that is enough water for now. If it soaked in rapidly, refill the berm. When the water has soaked in, leave it for a couple of days, then come back and inspect. Near the edge of the berm, dig a small hole with a trowel; six to eight inches is plenty. Check the soil you remove from this small hole for water content. If it is still sticky, you are good for a couple more days. If this soil easily clumps in your hand, you are still okay. If this soil is starting to dry out, then refill the berm.
After you have planted and done this a couple of times, you will quickly learn when to water.
Changing weather will influence your watering frequency. If a series of 30-degree days rolls in, your new tree will need more water. Conversely, if some cool and rainy weather blows in, the water requirements will naturally drop to some degree.
There is significant danger in over-watering—as much as in under-watering. When you have filled your berm and the water has soaked into the root ball, let the tree do its work and let the water cycle thru. A new planting continually soaked will drown. Ideally, the soil in the root ball would be kept damp; not too dry, not too wet.