Does it help to cut off trachy blooms?
Gerard feels that it makes no difference. He generally cuts off female trachy blooms so that he doesn’t have to deal with seedlings that germinate from fallen fruit.

Charlie told how he had been in communication with the horticulture department at the University of Las Vegas (Nevada), to find out about their recommendations for fertilizer regimes that will result in beautiful, healthy green foliage on all kinds of palms. Charlie joked that he gets many questions via palminfo@telus.net asking how to get palms that look as good as those at the Mercedes dealership on Broadway in Vancouver.

Charlie notes that K (potassium) deficiency can be a problem for palms in pots, and displayed Brahea leaves that developed when the plant was K-deficient. The leaves looked as if they had been lightly sprayed with yellow paint that left a pattern of fine dots. After remedial K-treatment, the next leaves on Charlie’s Brahea were beautiful, although the affected leaves did not recover.

Charlie recommends Betrock’s Guide to Landscape Palms for pictures of many nutrient deficiency symptoms.

Research has shown that NPK ratios like 20-20-20 result in too much P (phosphorus) for healthy palm growth. Thus, Charlie recommends fertilizers in which the middle number is lower. Here are some good choices:

• Smart-Cote Shrub and Evergreen Food 20-7-10. Charlie has seen this at GardenWorks and Art Knapps. He notes that it does not provide sulfur, copper, iron or manganese..
• Evergreen spikes (available at Home Depot)
• Lutz tree spikes. These are especially good because they do supply manganese in addition to other nutrients.
• Gerard noted that he uses mushroom manure on his palms, to good result.
  
  For more information try www.edis.ifas.edu

Charlie finished by noting that he uses palm food for his sago palms (Cycas revoluta) as well.

Alleyne Cook, Rhodomaster

Planting and watering rhodos and azaleas

Alleyne started by pointing out the currently glorious azaleas in Stanley Park. One of the keys to rhodo and azalea success is avoiding wet feet. These azaleas are in somewhat raised beds, in sandy loam.

Alleyne often waters rhodos by spraying the foliage, not the soil. In this way, the drip from the leaves provides the right level of water in the soil.

In response to a question about what species could be planted under rhodos, Alleyne said than any plant that forms a solid mat be harmful. For example wood anemones can be a considerable problem. Alleyne said that in Stanley Park, he would pile leaves under the rhodos. By spring, birds and squirrels had scattered and broken down the leaves to a good mulch. Mulch should not be piled around the trunk because it encourages weevils. Mosses, he added later, are a harmless groundcover.

Feeding rhodos and azaleas

Alleyne uses a 6-8-6 fertilizer. He notes that many brands with different packaging may actually contain the same product, so he hesitates to recommend a single brand. He cautions that you might want to apply fertilizer in a more conservative way than the package directs. For example, the grass as the Stanley Park Pitch&Putt was maintained in beautiful health with one-quarter the amount of fertilizer recommended by the manufacturer. As a result, Alleyne always dilutes fertilizer before application.

In response to a question about the advisability of mushroom manure on rhodos, Alleyne commented briefly on the limestone that is added to manure for mushroom culture. He himself does not use mushroom manure, but Gerard said that it can be OK if (a) you use aged material that has lost lime through rain, and (b) you don’t apply it too thickly.

Propagation by air-layering

Rhodos and azaleas develop roots well by air layering. Sometimes Alleyne will find a low-hanging branch on the parent tree, will bend it to the ground, and put a brick on it so that it will root. In general, though, he exposes the cambium of a branch and applies rooting hormone. He wraps the exposed part in sphagnum, then plastic, then window screen mesh (to protect from curious birds and squirrels).

He notes that air-layering works with a wide number of species, and mentioned success with Davidia involucrate (handkerchief tree). A question was asked about trying to air-layer large branches, but Alleyne said this should be no problem as long as you can get to the cambium.

In answer to questions

• When can you transplant rhodos? Virtually any time, because they have a well-defined rootball. It is advisable to avoid really hot weather, although even then, a transplant can be successful. Heel in the root balls if you can’t plant at once and maintain the soil moist by spraying the foliage to the drip point.
• When to prune rhodos? Right after blooming.
• When to prune jasmine? Right after blooming.

Nick started with the assertion that agaves are underutilized in exotic gardens. They can grow, he continued, in terrible soil, and several species are quite cold-hardy. Nick’s plants are around 15 years old, and live up against the south side of his house, under the eaves. They don’t like winter rain followed by frost, so Nick protects his plants with a large sheet of plexiglass that he simply leans against the wall, over the plants. He is careful not to let leaves touch the plexiglass, to avoid damage. In summer, these plants get full sun, and not much water.

Clearly, they like their conditions. Nick’s Agave havardiana is about 4 feet wide. In fact, it is doing so well that it somewhat crowds the slower-growing Agave parryi. The A. parryi can’t be too unhappy because it produces pups readily.