Pruning Ancient Species Roses

Dear Doyenne,
I would like to know if a Rosa eglanteria plant needs to be cut down in late winter/early spring. I live in zone 5. This is the second year that I have had this plant, so it is finally starting to have some height to it.

Thanks,
J.D.

J.D.,
Your Eglantine rose -- descended from a wild European species -- is one tough plant. I wouldn't prune it back this year, especially if it's just starting to put on top growth. Most old roses flower on wood produced the previous year, so they should be pruned only after they have bloomed. Next year, stems can be pruned to remove dead wood, diseased canes and weak or spindly growth. Give it time and it'll take off soon enough. Then, stand back.

Best, KL

Drought-tolerant Shrubs

Dear Doyenne,
Our entire Montgomery, Ala., backyard needed re-landscaping last summer. I've done most of it but am having trouble with one particular area under two very large old southern pine trees. The soil is very acid (from the pines) and also fairly dry and sandy. The area is also shaded from the east by a very large old Magnolia tree in the neighbor's yard, so it gets no morning sun and dappled sunlight part of the afternoon. What can I grow under pines besides more azaleas? I would like something that flowers at least part of the year.

Thanks,
Amy

Amy,
Amend the soil, start small, and be sure to water well until plants are established. A few shrub suggestions for drought-tolerant shade plants include: New Jersey tea (Ceanothus americanus), sweet fern (Comptonia peregrina), fragrant sumac (Rhus aromatica), Alpine currant (Ribes alpinum), Japanese kerria (Kerria japonica) and St. John's wort (Hypericum; we're big on H. calycinum out here, ad nauseum!).

Best, KL

Quality Soil Mix

Dear Doyenne,
I am going to establish a garden. I'm looking for quality dirt. I have found a place that will sell me 25% coconut fiber, 12 1/2% mushroom compost, 25% screened sandy loam and 37 1/2% garden compost. What does coconut fiber do? Is it good for clay soil? Does mushroom compost serve as fertilizer? If not, what should I use for fertilizer to add to the soil?

Thank you so much,
Jan

Jan,
That sounds like a VERY good soil mix. Coconut fiber has recently been added to a host of soil media as a renewable alternative to peat moss. It adds organic matter to the soil, increases its capacity to hold water, and also aerates the soil at the same time. Garden compost (and mushroom compost) is also a source of organic matter; as it breaks down it will encourage microbial activity, the result, humus.

However, both of these amendments will only work to break up clay soil if they are incorporated into it, rather than just dumping it on the surface. If you would like to add still more to the soil, a good all-purpose organic fertilizer will do, especially if you follow the directions and mix it in as uniformly as possible.

Enjoy, KL

A Maple for San Diego

Dear Doyenne,
I am very anxious to try a Japanese maple in coastal San Diego. We can get summer heat for 2-3 weeks in the 80s, but otherwise temperatures tend to be in the upper 70s. I have a shaded area next to a fence that is fairly well protected from winds. I have been told that Japanese maples do not do well in San Diego, but am wondering if there are any varieties that might be worth trying in my circumstance.

Thanks!
Karen

Karen,

Acer palmatum, the Japanese maple, is a woodland tree adapted to a climate with distinct subfreezing winters and warm humid summers. In Southern California, it does not receive enough winter cold to go dormant; also, it's subject to a host of diseases and pests. And as if that wasn't enough, the water in Southern California is high in salts, which tends to cause the leaf margins to burn. Get the picture? As an alternative, I can think of a fairly rare maple (consider the treasure hunt!) that is as graceful as Acer palmatum but a bit better adapted: Acer pentaphyllum.

Best, KL

Lawn in the Panhandle

Dear Doyenne,
We have a smallish backyard with a nice area for grass. We bought sod and installed it ourselves, watered and it died. We have had two professional installations, followed instructions and it died. The first time we are pretty sure there was a bug infestion, not so the next two times. The yard was rototilled and prepared well for the sod. It just dies right up the middle leaving some green along the edges. We bought some fescue seed in the hopes of getting a yard to root that way and of course it is not warm enough to seed yet. We have a sprinkler system and live in the Texas Panhandle. Do you have any suggestions for us?

Thanks,
Linda

Linda,
Sod can often be infected with diseases and fungus, which proliferate in the moist conditions when it is cut, stacked or rolled. For your area you might try to locate a source of Buffalo Grass (Buchloe dactyloides). It's tough, impervious to heat, drought and cold, and very easy to establish and maintain.

Best, KL

Obscure Australian Houseplants

Dear Doyenne,
We brought home an Australian brush cherry topiary (Eugenia myrtifolia) a month ago. We carefully followed the instructions and kept it moist and in part/full sun. However within 10 days the new growth shriveled and in the last couple weeks over 80% of the leaves dried up and started falling off. I'm feeling pretty pathetic about now, (I'm starting to think I should stick to raising dust bunnies) and am wondering if I can resurrect it or if maybe there was a problem before it even came to live with us.

Thanks,
Melanie

Melanie,
Your brush cherry (Syzygium paniculatum) is most likely reacting to the change in environment, from humid, sunny greenhouse conditions to the low humidity/low light in your house. I suggest putting the plant in the sunniest window you have, away from any central heat source. Water it when dry, but never so dry that the soil separates from the pot. During the growing season (May to August), add a bit of liquid fertilizer to the water every other time you water (you might also put it outside in a sunny location after all danger of frost has passed). Can you believe the plant is capable of 30'x30' in its native Queensland?

Best of luck, KL

Way Too Much About Phospherous

Dear Doyenne,
What are your favorite sources of phosphorus? How do you feel about inorganic vs. organic sources, and the use of these in near permanent drought conditions?

I live in the Phoenix area where the soil is salty. I know many people here like to use manure but I've also read warnings about the salts in manure. I think of it as a source of nitrogen, but recently read an article that says it is a good source of phosphorus as well. Some here say that phosphorus is a more important nutrient here than nitrogen because nitrogen stimulates vegetative growth and in the particularly hot dry times of year, plants have a rough time supporting new growth. I was wondering what you think.

Thank you,
D

D,
Aaaah, the old phosphorus question. Manure is indeed a very good source of well-balanced phosphorus. Animals, including humans, release phosphorus in their waste, hence the algal blooms that are associated with sewage. Because it has been broken down by an animal as it passes through, it is a particularly effective means of delivery to a plant. The salts associated with manures are from urea, which is the fastest component to breakdown; consequently, well-composted manure is usually not high in salts. (Except for chicken manure which is very high in urea and must be composted longer.)

Another source of phosphorus, if you would like to deliver it over a long period of time, is rock phosphate. It breaks down over time and combines to form phosphoric acid which is available to plant roots over a period of 3 to 5 years. It is also relatively inexpensive.

Non-organic sources of phosphorus, i.e. superphosphate, is basically the same thing, though altered chemically to release immediately as phosphoric acid. Unfortunately, the majority of it is wasted, as plants do not generally take up more phosphorus than they need. Consequently, it simply washes away into the soil or into drainage systems where it will accumulate (which brings us back to phosphates as a water contaminant and those pesky algal blooms.)

Using a good all-purpose organic fertilzer is the best way to ensure that plants get the right amount of each element that they require.

Best of luck, KL