Japanese Holly in Distress in Eastern Massachusetts

Question:
I planted a japanese holly about a month ago in the northeast corner of my house. I was watering it pretty regularly but went away for a week. When I watered it today, almost all of the leaves fell of. All I had to do was touch a leaf and it would drop although the leaves were still green and not browned. There are some tiny bud/flowers and the plant looks green. Has it been underwatered? overwatered? underfertilized? not enough sun? I would appreciate any advice.
Oh, and it might help if I told you I live in eastern massachusetts.

Answer:
A little transplant shock is typical, but this sounds much more severe. If your Japanese holly does not get quite enough sun then it will thin its lower, interior leaves. This interior thinning will also happen as plenty of new growth emerges from the tips of the stems and the plant grows larger. However, all that usually happens over a longer period of time, so I’m a little unsure as to why you are having so much leaf drop so quickly. I guess my mind then goes to other planting or cultural issues. I hope the rootball didn’t suffer too much damage when planted. Whether containerized or balled and burlapped it is important to keep the rootball as in-tact and protected through the planting as possible. You can and want to rough up the roots around the edges a bit to encourage them to grow out and down but never want to put too much pressure on the rest of the root mass. You should have planted the shrub so that it is level with the soil around it. Many used to advise to prep the hole twice as wide and twice as deep as the rootball, but now the consensus is that you do not want to dig too deep because you do not want the plant to settle and then have the crown of the plant below the soil line. If the shrub is planted too deep then you can run the risk of rot and the roots not getting the fresh air that they require. After planting I would “water in” the shrub by putting the hose on a slow trickle and letting it sit and soak the roots for an hour or so. Following that I would water a newly planted Japanese holly two or three times a week early in the day for an hour or two each time. For this, using soaker hoses with a battery operated timer can be a great help and make it easy on you. Regular and evenly spaced watering is a proper horticultural practice I can't talk up enough. If the shrub goes a week without water then obviously water it when you return, but do not then over-compensate and flood the plant. I always make the analogy that if you are dehydrated you do not then try and drink a gallon of water in one sitting, you sip, slowly and over a period of time, and then you will begin to feel normal again. In this respect plants are not all that different from humans. The dehydrated roots will not know what to do with such an excessive watering and you can do harm when you are trying to do good. Again, I might expect some leaf drop, but not like what you have described. And being away for a week should not send a woody shrub like that downhill so fast. On the remaining leaves, examine the undersides of the leaves and the nodes, the junctions where leaves and stems meet, and tell me if you see any sign of insects. Look at the base of the plant and make sure it is not too deep. If so, you might have to pull it out and replant it raised up a bit. For trees and shrubs people will tell you to err on the side of planting too high instead of planting too deep. Also, since this occurred so fast, call the nursery and explain the situation and ask if other people’s new hollies have been suffering too. There might have been something affecting the whole batch that no one had noticed before a bunch of them were sold. As far as winter hardiness, I believe that the holly should hold up where you are living. (Otherwise why would a nursery have sold it to you?). Some references say that they are only hardy to Zone 6 and I bet you might be a bit colder up there, but I am sure I have seen these broadleaf evergreens up that far.

Hmm, very interesting. Of course, if you have a digital camera you can take and email me some pictures and we can see if that helps me diagnose the situation any better. Think through the planting process you underwent and let me know if any other factors may have come into play. I’ll keep thinking too.

Evergreen issues in San Francisco, California

Question:
I have a garden with a large american elm, which faces two different evergreens, one a spruce and one a fir. On the branches that face the elm I have experienced lots of dropped needles. is there something about the roots or other element of the tree, like pheromones or some sense of closeness to other trees, which may be playing a role? this has been happening gradually over the last few years, and the evergreens in question are about 25 years old, with the very nearby elm pre-existent by at least as many years. but the pattern is striking, and would
suggest that to me. any advice would be appreciated.

Answer:

Well, sure enough, a picture is worth a 1000 words, but I hope my advice doesn't go on quite that long! First, I want to clarify the two evergreens. The tall, more cylindrical tree (images 2385 and 2387) is neither a spruce nor a fir. It clearly is a scale-leaf evergreen which means it is most likely an Arbovitae or possibly a kind of Chamaecyparis. Arbovitae are a popular screening tree for that kind of narrow location where everyone is trying to achieve more privacy and screening. The catch is that Arbovitae need full sun to be their happiest. Therefore the holes/patches of defoliated branches are clearly signs to me of too much shade. The other tree (2386 and 2392) you are right, is either a kind of spruce (Picea) or fir(Abies). Here is a quick way of figuring out which one it is. Grab a piece of branch that has both needles and bare stem, meaning a piece closer to the center of the tree. Next, pull off a few needles one at a time. Spruce, when you pull a needle, leaves a little bump, or "peg" where the needle emerged. Hence the catchy phrase, "Picea have pegs". If you pull the needles and they take a tiny piece of the bark with them, leaving a clearly "circular leaf scar" where the needle emerged, then that is a fir tree. Generally people say that spruces are more hard and prickly and firs are softer and more fragrant, but typically that is not enough for a concrete plant ID. However, either way, both spruces and firs, yup, like sun also. Sounds to me, Aaron, like it's not an issue of a disease at all. And yes the space is limited, and for the roots as well, but honestly I think the problem is much simpler. The elm is slowly shading out the other two trees. It grows as fast as the other two, especially if the other two don't get enough sun, its canopy casts more shade, and it makes sense that you have been watching this gradually happen over the last five years. The Arbovitae is going to continue to lose needles on the side facing the elm because that's the shadiest. The fir/spruce/? will also continue to drop needles from the base upwards. You have new growth on the tips of both evergreens so they are still alive, but just getting out competed for the necessary sunlight. At a cost arborists may be able to come in and thin out the canopy of the elm to allow a little more light through, but it might be worth thinking about what you want to do in the long run. Certainly you can cut the dead branches off the evergreens because they will not leaf out again from those spots.