Hi everyone. I am new to tree planting and have purchased two wonderful looking trees. 1st one is a Korean Maple and the 2nd is a Japanese Maple. I am having some problems with the leaves on the Japanese Maple tree (Japanese Emperor Acer Palmatum) which I planted about 3 weeks ago. Height of trees are about 5-6 feet tall. The weather here has been hot and sunny for about a week and the leafs on the maple are starting to dry out with a few spots on the inside of the leaf. I planted them using a (Myke Tree and shrub growth supplement) using landscape fabric and white rock on top for looks. I water my trees everyday in the evening and was told that using a lawn sprinkler can cause the leafs to dry out or leave water spots that can damage the leaf? So now I do not water grass until the sun goes down. Now that most of the leafs are damaged will this have any effect on the tree in the future? Should I be using any type of tree fertilizer on a newer planted tree? Hopefully I am not doing anything wrong, any advice would be helpful Thanks Rob
Japanese maples need light shade, not full sun, and it may be better for you to move the tree now, before it gets established, to another area. Watering is fine for trees in general, but if your maple ISN'T in dryish gritty soil (and I don't think BC has a lot of that somehow), and it is in some shade (hopefully), you might want to back off on the watering a bit... they can stand to be just a bit on the dry side, like pines, especially if it rains a lot there.
Maples need a good sandy loam that drains well, and do not need to be watered that frequently. Consider the amount of water that your two maples are getting when watering the grass as well. Check out this thread: http://www.botanicalgarden.ubc.ca/forums/showthread.php?t=13835. I assume that along with Acer palmatumEmperor, you also have Acer pseudosieboldianum, which would have the same cultural requirements. I do not know what Myke Tree is, but hopefully the shrub growth supplement was good for the roots. Maples also do not need to be fertilized very frequently, and often in the Maples forum it is recommended that the nitrogen component of the fertilizer be low. It is unlikely that your 'Emperor' received too much sun that week if you are west of the mountains. If the sprinklers were getting water on the red leaves in the heat of the day that week, then that could have burned the leaves, but I recall reading some controversy regarding that issue here on the forums. It is not clear that you are sure that this occurred, but if it did, it will not have a long-term effect on the tree. This may not be the cause, however, since you mentioned that the leaves are starting to dry out with a few spots on the inside of the leaves. Did you mean on the underside of the leaves? Most of the leaves are affected; can you post a photograph?
