New Dogwood - Leaves turning brown

[mollybeans]

I live in Michigan (zone 5). I just planted a 7' flowering Dogwood (Cornus Florida 'Cherokee Brave') less than 2 weeks ago (mid July). I purchased it at English Gardens, it was in a plastic pot. I have good light sandy soil, and I added peat when planting. I also used root starter liquid fertilizer (diluted w/water). I followed planting instructions well. I have been watering it religiously - trickling with hose for at least an hour twice a week, plus using sprinkler, and testing soil with my finger. It is is in full sun, and it has been extremely hot - 90-100 degrees everyday last week.

Problem: Within a couple days of planting the leaf tips started turning brown. Then a patch of leaves started turning purple (their autumn color I believe). Little by little more leaves are getting brown tips, then the margins turn brown and crumbly. Some leaves have holes/cracks down the center. Some have turned completely brown and fallen off.

Does anyone have suggestions on what is happening and what I should do? I called the MSU hort.hotline and they said it could be transplant shock or effects from the high heat (many plants are suffering right now). They are also sending me some info on anthracnose. I'm hoping that my brand new tree does not have a fungus.

Any and all suggestions are welcome! Thanks in advance!

[eklawun]

I hesitate to reply because I am not an experienced gardener at all, but I wanted to let you know that I share your plight (with newly planted shrubs) and thought I would pass along the info given to me at the nursery here.

My guess might be not enough water for the amount of heat you have been having? How big was the root ball? I was told to keep the shrubs moist and water on a daily basis until they got rooted in. I am not sure how long that takes, but would guess more than two weeks?

We also have a maple in the front yard, planted last fall that was accidentally cut off from the sprinkler system for three weeks at the beginning of June and its leaves look like what you are describing, except that they haven't turned fall colors. The most noticable thing is that when you look at the tree as a whole, the south side (where our hot winds blow) looks markedly worse than the north side and the outermost leaves look worse than those nearer the trunk. One of the landscape guys in the area told me that the tree (maybe a bit bigger than yours) would be drinking about 5 gallons a day in this heat and with the wind. I'm not sure how knowledgeable he was, but that was what he said.

I would probably ask at the nursery where I bought it...

Perhaps one of the experienced folks here will chime in soon too!

I would desperately love to have a dogwood, but I have no shade for it and will have to plant other trees first before I can hope that one would survive down here in Oklahoma.

Good luck and let us know what you find out.

[hendi_alex]

I have several small but established dogwoods which are between two feet and four feet tall. All have brown edges on the leaves this year. I'm in light sandy soil, the temperatures have been very hot, and it has been very dry. So this sounds to me like water stress. My response has been to place my hose on very slow trickle and rotate it from plant to plant each day. This seems to have stopped the browning of leaves from progressing.

[hendi_alex]

I have several small but established dogwoods which are between two feet and four feet tall. All have brown edges on the leaves this year. I'm in light sandy soil, the temperatures have been very hot, and it has been very dry. So this sounds to me like water stress. My response has been to place my hose on very slow trickle and rotate it from plant to plant each day. This seems to have stopped the browning of leaves from progressing.

Dogwood trees are shallow rooted with a fairly small root ball, so the tree will likely need to be watered during dry periods for a couple of years. This year I would keep the soil constantly damp but not soggy. Also perhaps let the hose trickle just outside the root ball, so the roots will grow toward the water source. Finally, place the drip on different sides of the tree each time you provide long slow watering.

The brown edges on the tree will not affect it long term. The leave may even drop early this year, but that should not be a problem either, IMO.

[bullthistle]

What no one has addressed besides the heat is how the plants were planted. The fastest way to kill anything living is to deny them the right to live. When backfilling it is important to tamp down the soil with the end of your shovel not the heal of your shoe. When there are air pockets in the soil that will kill the plant faster than anything you can think of. Planting plants is a laborious process and sometimes people take shortcuts but they can lead to disaster.