Awabuki Hedge
Plant Diary

November 2007 - Our hedge outside the pool area has created more problems than we bargained for. Its primary purpose was to act as a tall privacy screen for our pool and tropical garden. It runs over 100' in length and eventually needs to be at least 8' in height. At the recommendation of our landscaper/nurseryman, we used Awabuki Viburnum, a fast growing, tough shrub that can reach 15' to 20' in height. In order to make an immediate impact, we opted to purchase 15 gallon plants, instead of the typical 7 gallon pot variety.

As soon as the landscaper had the 20 plants in the ground, we noticed that several had started to wilt. Granted, it was a hot, humid summer afternoon, but to see such immediate wilting should have tipped us off that the plants would need special attention. After a couple of days of hand watering, I put in two drip lines on either side of the Awabuki along the edge of where the pots had gone into the ground. I set the drip system to run each morning. Within a few days, the plants were back to wilting in the late afternoon and showing signs of significant leaf drop. I reasoned that I had planted the drip lines too far from the plants and that I would have to compensate by more regular hand watering until the plants settled in.


The Awabuki hedge is on the left.

In retrospect, I was suffering from a bad case of "gardener's hysteria" - too many false positives that lead me to over react. Seeing the Awabuki wilt, I responded with additional watering - running the drip system longer in the morning and hand watering in late afternoon. However, after a day of rain I decided to turn off the drip system, only to find the Awabuki wilting by the next afternoon. A few days later the Awabuki experienced significant leaf drop and we assumed it was caused by the wilting. So we increased the watering to the point where the soil around the hedge row felt like a swamp under foot. After three weeks several plants showed increased stress and had lost most of their leaves. I checked their root systems and found that the plants were not sending out new roots. Time to panic.

I called back the landscaper to see what could be done. By this point it was clear the plants were being over watered, but I didn't dare cut back for fear of more wilting and leaf drop. We both noted that there were signs of mildew and fungus on the plants, leading the landscaper to apply two treatments of systemic fungicide. A few of the plants appeared to have powdery mildew from whiteflies, so I applied an insecticide. Regardless, nothing seemed to work and the plants were looking awfully pathetic. In desperation I began a weekly treatment of liquid fertilizer to see if I could kick start the roots and new leaves. (BTW - there is a great video from the University of Florida on Awabuki diseases.)

Awabuki
Recovering Awabuki (December 2007)

December 2007 - After three months of constant attention, way too much hand watering and the replacement of three of the Awabuki that looked particularly sad, things are finally calming down. Most of the plants are sending out new leaves, the fungus has disappeared, I've cut out the hand watering and I only run the drip system twice a week. My guess - we should have opted for the 7 gallon pots. The 15 gallon plants were way too stressed and demanding. The wilting lead to too much watering, the swamp-like conditions lead to spreading fungus, which compounded the leaf drop, which impeded the development of roots, which lead to more leaf drop, which lead me to water even more, which lead to more leaf drop. Gardener's hysteria.

I've now calmed down and so have the plants. Let's see what happens this Spring.

January 2008 - In my eagerness to get the Awabuki back on track I nudged them along pretty aggressively with liquid fertilizer during November and December. The fertilizer helped tremendously, except I now had a profusion of new tender leaves just when the threat of frost was greatest. Sure enough, the freeze on January 8 killed off a good portion of the new leaves, since they did not have enough time to harden off. Awabuki
March 2008 - The freeze was a minor set back. The Awabuki are now sending out a profusion of new leaves. The hedge is even beginning to fill in.
July 2008 - It looks like all the hard work and compulsive caring is finally paying off. The hedge is filling in nicely and beginning to fulfill its purpose. There was a minor scare in May when several of the plants showed signs of black spot. However, a couple of applications of a fungicide stemmed the outbreak and there are now few signs of its effect. Viburnum Hedge
Awabuki Viburnum Hedge

See also:

Viburnum