My 3 year old camellia has struggled through the atlanta drought, came back from death, added about 2 feet of growth, and now is showing signs of some sort of disease. Can anyone identify it, and tell me how to treat it?
The leaves were too far away for me. I saw something resembling a fungal infection but it's hard to say. Can you post a close up of the leaves uppper and lower surfaces? Luis
sorry it took so long to respond. finally got the camera out to take some shots. I see atleast three distinct things on the plant - holes in the leaves, splotchiness on the leaves, and what looks like burnt edges. Please click the following link to view the photos. I appreciate the help.
newbie gardener blog
Hello, reuscam. Here are a few comments about the photos...
Photo #1: an unknown pest (an insect, worm, etc) has obviously chewed on the leaves. The chewed leaves also have some dark spots, signs of a fungal infection. It could be the result of an opportunistic fungal infection taking advantage of the chewed areas or it could be minor/common problems caused by such things as watering the leaves directly, too much rain, too much humidity, etc. The problem does not seem like a big deal at this point so I would monitor the leaves and take further action only if things get much worse. One of the leaves looks distorted, probably caused by aphids.
Photo #2: I would add 3-4" of mulch to the camellias. Sprinkle some mulch up 12" away from the main trunk. On older plants I would have said up to the drip line or so but these are new kids on the block so I would start with 12". Of course, I live in Texas where the weather is hot and mulch applied away from the trunk is always welcomed by camellias in the Summer!
Photo #3: more leaf damage....pests sometimes like to take a bite and then they leave the area. To determine if they are gone or if they are still in the area, use the oldest pictures taken as a reference point to determine if the damage is getting worse or not. If it is changing and keeps getting worse, you will need to identify the culprit. In many cases, these pests hide under rocks/mulch/etc and -since they are nocturnal- damage the leaves at night. This means you might need to check the plants at night (look under the leaves and around the main stems).
Photo #4: signs of fungal infection again; I would remove the worst looking leaves and dispose in the trash, not the compost pile. There are some white(or gray?)-ish spots. Sometimes these are caused by powdery mildew, too much salt or too much fertilizer. If the white spots were smaller and randomly dispersed thru the leaf, I would even suspect tea scale.
Photo #5: reminds of powdery mildew on some euonymus that I used to have. Weird if it is powdery mildew because PM is not common nowÂ.more common during the summer months (unless the leaf damage in the photos happened last year). Sanitation practices can be used with powdery mildew. You should next try horticultural oils next and your last line of attack should be fungicides. Choose fungicides containing one of these active ingredients: myclobutanil, triadimefon, propiconazole, thiophanate-methyl, triforine. To prevent the fungi from becoming resistant to the fungicides, apply fungicides with different active ingredients (use myclobutanil on week one, triadimefon on week two, etc).
Scale can be controlled using organic methods such as removing infected leaves (photo #4) & releasing lady beetles or beneficial wasps (called Aspidiotiphagus or Aphytis Diaspidis); you can also prune to improve air circulation in the center of the plant. Horticultural soaps and oils (Bonide All Season Spray Oil, Green Light Horticultural Oil Spray, etc) should be used next (because they are less harmful to the scale predators) but remember to apply these to the top and bottom of the leaves. Use insecticides as your last line of defense.
Be aware that for a definite answer, you can also take leaf samples to a nearby local nursery or to your Agric Extension Service for analysis. Send the samples in sealed transparent plastic bags.
Thanks Luis. I ended up taking a few different leaves to the local nursery. The nice lady there told me it was all signs of fungus, the holey leaf being black spot (I think). She prescribed a fungicide. I tried using it, but the pump sprayer she sold me was a piece of junk.
I went on to mulch to the beds - something we planned to do even before your advice. One question I had, you recommended 12 inches out, but I've also heard not to cover the rootball. Which is correct? We ended up leaving the 6 inch diameter rootball unmulched and touching air, and everything outside of that mulched fairly deeply.
Thanks again for the help.
I was having a really bad time with my Camellias. Leaves falling off, yellowing, just a dreadful sight. I really thought I had a bacterial infection or fungus. My local nursery told me it was because of m soil condition, too much Clay. He prescribed Copperas. I applied it as stated, and a week later came back again. You need not even work into soil. Just sprinkle it all around the base and drip line. I then used a 10-10-10 fertilizer every two weeks, and copperas every two weeks... now my camellias are huge and happy and full of life. Fish emullsion on the off weeks...Wonderful!!!
reuscam, luis meant for you not to cover the root ball and to apply the mulch over a reasonable circumference around the tree trunk. At least that's what I think he meant, lol. You are absolutely correct about not mulching over the root ball itself, but outside of it.