Camperdown Elm

Dear Doyenne,
I have a very nice Camperdown elm growing in my backyard that I love but have no clue as to how to best keep it healthy and happy. I live in Portland, Ore. The tree is about 7' tall, I'm not sure of its age, maybe 30-40 years, guessing from the history we were told of the tree when we bought the house. How sturdy or not are these trees? Am I supposed to be doing anything to train the drooping branches, like support them so they will hang further out from the main trunk? Is there any pruning I should be doing, other than removing deadwood and keeping a "doorway" shaped from the hanging branches? I have noticed an orange-rusty looking coating on the tree. Is moss growing on the trunk bad for the tree?

Thank you,
Cindee

Cindee,
Sounds like you're taking good care of it. You did the right thing by picking up the leaves and you should continue to do this. I might also suggest that you keep the tree well-watered during the summer, as the species is native to areas with summer rain and our summer drought can stress it big time. Water by placing a hose at the base (opened to barely a trickle) and leave it on for several hours once every couple of weeks. Prune out only dead wood, unless you're shaping the tree. Do this in the winter when the tree is dormant. Camperdown elms are generally very sturdy trees and, unless they are ancient, will not require support. Don't worry too much about all that gorgeous moss; it should have very little effect on the tree.

KL

Transplanting a Tree Fern

Dear Doyenne,
Well, maybe this isn't a strictly "why-did-my-plant-die?" question, but since I am wanting it to NOT die, I thought maybe you would help. The question is regarding a (Australian?) tree fern which may be about 20 years old. It started its life in a half barrel, and spent the bulk of its time in that barrel situated next to the house wall on the patio where it got little direct sun. We subsequently transplanted it out of the barrel into a narrow (30") planter area, and there it has stayed for the last 12-15 years. This planter is against a wall facing east, in a protected ell. In the last few years it has started getting messy with the "fern dust" and we now want to transplant it into another half barrel, this time a larger diameter, and shallower depth. We live in the San Francisco Bay Area

When and how should we transplant the fern into the new barrel? Should it be staked or should the root area be anchored in some way to keep it from tipping or other stress while becoming established in the new barrel? Should it be kept wet/moist/or on the dry side initially? Fertilizer?

Thank you,
TB

TB,
The tree fern should be fine in its new barrel. Just transplant it into new soil with as little root disturbance as possible. Also, remove some of the oldest and largest fronds, as this will help it establish faster. If wind is an issue, until it's sturdy and stabilized, keep the fern firmly in place with stakes on both sides. And finally, be sure it stays well-watered until you see new growth; consider treating that crown with a light mist on hot dry days.

Enjoy, KL

Transplanting a Japanese Maple

Dear Doyenne,
I need to transplant a 50-year-old Japanese maple bush (A. palumatum) to make way for a deck. The new spot has the same sun/shade/wind ratio as the current spot. The plant is currently very healthy and large, perhaps 8-9 feet in diameter, 4-5 feet tall. I'm located in Portland, Ore., in Climate Zone 6.

When is the best time to transplant? What is the best soil preparation? How much pruning, if any, should be done before transplanting? What is the root structure? Is it shallow & wide, or deep and long?

Thank you for your help.
Lisa

Lisa,
I'd vote for transplanting in late fall, when the tree is dormant. Japanese maples prefer a loamy, well-drained soil that is slightly acidic (not an issue in Portland). They don't usually require heavy pruning, just the standard crossing and dead branch removal, which I'd do before transplanting. Keep in mind that being a 50-year-old specimen, it may well suffer transplant shock. That's why I'd recommend root pruning about a year beforehand, which will give it time to grow some nice new fibrous roots. This truly surgical strike may do a lot towards your tree's survival.

Good luck! KL

Pruning Hydrangea

Dear Doyenne,
I have been told not to prune my Nantucket hydrangea bush after the bloom or in the fall. It has grown out of bounds and I don't know how to shape it. I want it to bloom. Can you tell me what to do and when?

Thanks,
Patricia

Patricia,
'Nantucket' is a cultivar of the bigleaf hydrangea (Hydrangea macrophylla). The flower buds on this group are formed on the previous year's branches, which means that pruning should be done right after flowering (except for dead branches, which you can prune in spring). Sometimes, it's necessary to remove old canes (branches) to open up the bush, a practice called rejuvenation. If you do this over a three-year period, removing one-third of the old canes every year, you can start to assert control and not loose the blossoms all at once.

Enjoy, KL

Grass Removal

Dear Doyenne,
What's the best and safest way to replace a hard-to-mow area of grass surrounding a tree with a bed for shade-loving plants? I have a rototiller, but I don't want to hurt the tree. Can I use a grass-killer within the tree's drip line, or do I need to strip the turf, then add a topsoil/compost mix? How much or how little digging can I get away with? How deep can I go? Should I try another tactic and cover the area with something (e.g., wet newspapers, black plastic, then shredded bark mulch or gravel) and let time do its job? How much topsoil can I then pile up near to (but not touching) the trunk?

Thanks,
Rod

Rod,
The best and safest way to remove grass under the drip line of the tree is to smother it with 4-6 inches of woodchip mulch. To speed up the process, lay a few layers of newspaper (no colored paper) on top of the grass before you apply the woodchips. Plants can be added a few weeks later. There is no need to add additional soil. Adding more than 1-2 inches of soil, or rototilling under the drip line of a tree can -- as you imagined -- damage many of the small feeder roots that supply water and nutrients to the tree.

Enjoy, KL

Plants for a Shady Bank

Dear Doyenne,
I have a steep-sloping bank which faces West and gets maybe 3 to 5 hours of sunlight in the afternoon. The top of the bank is dense with trees which overhang it. So, anything I plant grows leggy and towards the sun. What can I plant, that is dense, will cover the steep bank and give me lots of color? Or, should I terrace it and go with hollies, mountain laurels etc. The bank, located in Baltimore, Md., is irrigated with a sprinkler system.

Many thanks,

John

John,
You don't know how lucky you are to have an irrigation system in place! Your sloping bank would be more difficult to get plants established without it. However, soils are probably variable throughout the site, though I'd guess usually shallow, acidic, and somewhat deficient in phosphorus. It would help to amend the soil as you are planting, and add a layer of organic mulch around the base of plants for added protection until established. Large sweeps of woodland plants, such as bloodroot, coral bell, tiarella, Turk's cap lily, astilbe, lungwort, ferns and geraniums would add the most color and diversity to your slope. Ferns and rambling vines would provide additional cover. Terracing is expensive; all you need are the right plants.

Enjoy, KL