Documents: Latest From: The Real Dirt:

Blue Bean, Magnolia, MYKE &Ants

Rare plant for you: Blue bean (Decaisnea fargesii); triple super-phosphate and Myke; controlling of ants outdoors; topsoil; and the lack of Magnolia flowers in southern Ontario this year!
by Art Drysdale
by Art Drysdale


Art Drysdale, a life-long resident of Toronto and a horticulturist well known all across Canada, is now a resident of Parksville, British Columbia on Vancouver Island, just north of Nanaimo. He has reno-vated an old home and has a new garden there. His radio gardening vignettes are heard in south-western Ontario over radio station Easy 101 FM out of Tillsonburg at 2 PM weekdays.

Art also has his own website at

May 20, 2007

Above: the fruit (beans) of Decaisnea fargesii is likely the plant’s most attractive feature, photo courtesy Thompson & Morgan Seeds; below, five shots of Magnolia shrubs/trees in the GTA: first, an almost flowerless tree in East York; second, two shots of one of the newer species with a few flowers, on the same East York property; fourth, another almost flowerless M. soulangiana, this one in Rosedale, followed by a close-up shot of two of the few flowers on the tree.
Author photos.

Louise Wall, a good friend here in Oceanside (Parksville/Qualicum Beach), wrote with a question about a plant that I had never heard of previously so I though the results of my little bit of research might be of interest to others as well. Here’s the question: “What can you tell me about Decaisnea fargesii (blue bean)? I bought one and all the tag says is that it is a deciduous shrub to 5 m (15+ ft?) tall with compound leaves which emerge dark-green, and attractive yel-low-green flower panicles, followed by large metallic-blue bean pods. Full sun. Cannot find anything about it in my garden encyclopedias except that it needs minimal pruning. Would like to know how wide it grows, when it blooms, and what zone it is. Is this the same plant that sometimes is also called Dead Man's Fingers?”

Well Louise, you do find the interesting items! Decaisnea or blue bean comes originally from Asia. It is a deciduous shrub growing to 4m by 4m at a medium rate. It is hardy to zone 5 on the US hardiness map which means it will definitely be hardy for Louise in Qualicum Beach but in Ontario it will be a bit of a gamble, since the US zone 5 is a bit comparable to the Canadian zone 6 (on the 1967 map) which just includes the Toronto area. It is also indicated that the plants are frost tender. It is in leaf from April to October, in flower in June, and the seeds ripen from September to October.

The plant is apparently not fussy as to type of soil (sand, clay or loam), or as regards acidity, growing in acid, neutral and alkaline soils. It is also not choosy about sun/shade, growing in most locations except full shade, but it prefers partial shade. In full sun, it will need to have constant availability of moisture.

The plant may take several years before it flowers and sets fruit. The fruit (beans) are somewhat like bright blue beans or sausages. They grow to a length of 10 cm (4”) and are variously described as tasting sweetish, insipid and not great!

I am not sure where Louise got the name Dead man’s fingers, but as far as I know that common name applies to a type of seaweed, Codium fragile, that grows in inter-tidal waters. A whole bunch of it is actually a one-cell structure.

Thomas Roberts in Northern Ontario wrote on May Day: “I have just discovered you. How wonderful. I recently read your article about bone meal and super phosphate 0-20-0. I am giving everyone interested copies of your article. But I have run into a problem. Because I am a little isolated being in the north in Sault Ste. Marie Ontario, I have only been able to find [triple] super phosphate 0-46-0 at one local outlet. No one has 0-20-0 although one store I am giving your article to said they might look into it. The outlet that sells 0-46-0 said I can use it but not use as much. How can I make sure I use the right amount and in the proper way without damaging the root system (or will it even hurt the roots) of some one-foot cedars and burning bush shrubs that I have just bought and would like to plant soon?

“One outlet says they are getting a product called Myke. It is supposed to help the plants get all the nutrients from the soil. The sales person said she planted two identical plants last year (one with nothing added and one with Myke) and the one with Myke was incredible compared to the other. Should I use Myke instead of 0-46-0 if that is better? I would appreciate your comments about these two products and any advice you can give.

“I know you are a busy person but hope to hear from you soon so I can plant my shrubs. Thanking you in advance.”

It is hard for me to believe that a farm dealer (that is where you should be looking) would stock triple super phosphate and not the regular super phosphate. However, if you are considering using a Myke product (I would suggest the one designated Trees and Shrubs since that is what you are planting), then I would not suggest any high phosphate fertilizer, even liquid transplanters (e.g. 10-52-17). These formulations actually make it more difficult for the mycorrhizal fungi in Myke to do their work. The product should be well mixed with the soil at the time of planting, following the directions on the package. That would be my suggested way to proceed.

Gloria Bourne’s is the next question I have, and it goes back to May 3. “I know that this is a very busy time of the year for you, but I would really like a response a soon as possible. For the past three years I have had two ant nests, one in my front garden and one in the back. I have tried everything from hot water, powders from the garden centres, soap, sticky products, but nothing seems to work, I am just in the process of turning the soil over and already I can see the nest forming and the ants running around. Mr. Drysdale do you have any suggestion? A couple of years ago you told me the cheapest way to get rid of skunks by placing bottles of water around the area and the reflection from the bottles scared them away. At this point I am not even worried about cost just so long as I can be rid of the ants for good as they make a mess of flowers.”

The answer for most ants is fairly easy. Wilson GrubOut is still available from the Nutrite company. Its basic ingredient is Sevin or Carbaryl (22.5%) and it is relatively safe (except for bees, and its use should be curtailed on flowering crops when the flowers are out). Follow the label directions for ants and repeat the application in about 20 days.

Aimee G. Cheung too asked a fairly simple question, but she did not say in what area of Toronto she lived. Here is her note: “I came across your website. I am a former BC resident who now lives in Toronto. I am trying to locate clay soil (and having a hard time). Would you know where in the Ontario area I can get my hands on clay soil? I'm going to use it for grading. Thanks!”

Getting good topsoil (I don’t think she really wants clay soil, unless she is going to cover it with a fairly good layer of topsoil) is not always easy. One of the suppliers I recommend is Arnts Topsoil who have two locations east of the GTA. One is on Brock Road in Pickering where the telephone number is: (905) 683-0887.

Finally this week, Murray Funk wrote on Monday, saying “You've probably already had this question numerous times, but I've noticed that this has been the WORST year in my memory for Saucer Magnolias. Any idea why? Thanks.”

Murray is certainly correct. My friend, horticulturist Larry Sherk commented upon this over two weeks ago, and then two weeks ago, avid gardener Laura Grant called in to my programme saying that it was not just in the GTA, but as far south as Niagara-on-the-Lake: the common saucer magnolias (Magnolia soulangiana) just have almost no flowers this year. I am virtually certain it had to do with the mild winter you had until mid January when it got very cold, and stayed cold for some weeks. That likely encouraged the trees to begin a slight opening of the flower buds, which were then killed off in the late cold spell. In my recent visit I did notice that the worst-affected are the straight species, and that some of the hybrids, such as those with ladies’ names seem to have come through somewhat better. Nothing needs to be done and hopefully next year the same scenario will not be repeated.

  • New Eden
  • Kids Garden
  • Plant a Row Grow a Row