Tropical Overwintering - An Experiment

Overwintering tropicals can be challenging if you don't have a heated greenhouse. I've had this narrow leaf ficus since about 1990.

Here's what the tree looked like a couple of years after I purchased it.

Each year I have to figure out a way to keep it happy when the weather cooled. A few times I've lucked out and found heated greenhouse space. But usually it ended up somewhere in my house (along with a fair number of spider mites) and emerged in the spring looking non-too-happy.

Recently we moved into a townhouse, which will be our temporary home until are new house is completed. My office area includes a bank of windows that allow in a fair amount of light. Although the space is tight, I thought it offered a good spot for this year's overwintering experiment.

As I mentioned, spider mites are often a problem with the indoor overwintering of this tree. Inside humidity levels are usually quite low, especially with the heating system is running constantly. These conditions seem to provide an ideal environment for spider mites.

To head-off this pest invasion, I treated the ficus several times with highly refined horticultural oil. I also used a non-toxic (but expensive) soil drench to clear out the ant colony that had taken up residence in the pot.

To keep humidity around the tree as high as possible, I purchased an washer overflow pan from HD. Hopefully this reservoir of moisture will help to offset the townhouses dry air.

A few years ago I overwintered the ficus at a bonsai nursery that used propagation matts to boost the temperature in the root zone. The ficus responded well to this set up, so I decided to use a similar approach in my own set up.

I purchased a matt that is designed to warm to 10 to 20 degrees above the ambient air temperature. (It has to be elevated above the water in the tray to work properly, however.) I placed a layer of heavy duty foil under the matt to help reflect the heat up to the pot.

Here are a couple of pictures of what this set up looks like.

If you have any ideas for how to improve this setup, let me know.
  

Colin Lewis Announces Bonsai Classified

Colin has started a buy/sell section on his bonsai forum. It's a place where you can post an item or make a purchase. Any comments on this?

Interview with Nick Lenz

I found this to be not only hilarious but also very thought provoking and informative. Here is the link http://bonsaijournal.com/nick-lenz-profile.php#

Rusty

Mycorrhiza

Trees rely on mycorrhiza to help deliver micronutrients to their root systems. Mycorrhiza occur naturally, but you can also inoculate your trees during repotting by adding commercial grown fungi.

One source, recommended by Rodney, is Bio-Organics (http://www.bio-organics.com/). They offer 1.5 lbs (trial) and 3 pound containers with several versions of the product. I suspect the micronized might be a better product for bonsai. The company also offers a new product that include micronutrients.

Even the trial size is quite a bit of material. This might be a good product for a group buy.

Non-toxic soil drench

I've been looking around for a non-toxic (to me) soil drench that could be applied without donning a HAZMAT suit. I came across a product called SNS (Sierra Natural Science) 203 Pesticide.  Here is a portion of the product description:

BGH approved! SNS 203, 217 and 244 all did phenomenally well in BGH-hosted trials. Highly recommended!

SNS-203™ Concentrated Natural Pesticide Soil Drench is made up of pure Rosemary and Clove botanical extracts. The botanicals are all food grade GRAS (generally recognized as safe) materials. SNS-203™ Concentrated Natural Pesticide Soil Drench is exempt from EPA registration under minimum risk pesticides exempted under FIFRA section 25(b). Coco Soil Safe. 


And here is a link to the online retailer: http://www.bghydro.com/BGH/itemdesc.asp?ic=PCSNS20316&eq=&Tp=

Any thoughts on this product? Reservations about using? Let me know.

Slow Release Fertilizer

There was quite a bit of discussion about fertilizer, and its role in promoting the growth and long-term health of bonsai. Rodney suggested using a slow-release fertilizer in combination with the usual practices. His current favorite is Florikan 14-14-14, which lasts 3 to 4 months after application.

It is a commercial fertilizer, but consumers can buy it through online and brick and mortar nurseries. It's available through A.M. Leonard at http://www.amleo.com/Florikan-Controlled-Release-Fertilizer/p/VP-FLK/. Since it's a commercial product, it is sold in large quantities (and with a corresponding price).

The consumer version of this product is sold under the Dynamite brand.

Notes from September 11, 2010

Another Great Session

Sorry for the delay in posting my notes from our last meeting. It has been a hectic couple of weeks.

Also, I had planned to take pictures during this session, but discovered after I arrived that my camera's battery was dead as a doornail.

Is a Kingsville or Not

Rodney gave some pointers on identifying Kingsville boxwood. If I understood correctly, Kingsville are often cultivated from cutting. Mature Kingsville often throw sports that are actually represent hybrid growth. If a sport is taken as a cutting, the resulting plant won't be a true Kingsville but a genetically compromised hybrid.

If you want to know whether a tree is Kingsville or something else, look carefully at the bark on the trunk. It should be white. The leaves tend to be roundish. A hybrid will have a darker bark and the leaves will be more elongated (as a rule).

If you are working on a boxwood, it's best to prune from the top and work your way down. This approach facilitate achieving the type of live oak-tree or magnolia style that seems to work well with this particular plant.

On a related note, cotton seed meal is an ideal slow release organic fertilizer for boxwoods (and probably other evergreens I'm sure).

If you're repotting a boxwood, strive for a mix that retains some moisture. Boxwoods have a very fibrous root system. If the mix is too porous, the root will dry out quickly, which will stress the tree significantly.

Bud Growth on Shimpaku

My Shimpakus look more like runty bushes than trees, so I was glad to hear that you can stimulate back budding by cleaning the bark and wiring. A wet toothbrush is good for small areas. A bonsai wire brush is best for larger areas.

In both cases, it's important to brush gently. Avoid using any of the wire brush you might find at the home store. They are much to course for this type of cleaning.

Another good thing to know: you can fertilize Shimpaku in the fall. (I'm assuming when the temperature is below 90 degrees.) Any new growth will harden quicken and overwinter just fine.

Unwanted Lower Branches

You should be cautious when removing a large branch that is low on the trunk. If you remove it in a single cut, the tree can be severely traumatized. Dieback into the trunk may result. It's much better to leave a stub, allow the stub to atrophy, and then remove any remaining material.

Anchoring a Repotted Tree

Most of us use aluminum or copper wire to anchor in a tree after repotting. Rodney suggests using cotton string, which will rot away by the time the tree's new roots have spread out into the pot.

You typically thread the string through the tree's root system and then tying it off. I'm tried this technique myself at different times, and I can see the advantage. My anchor wire tends to stay on--forever.

Jins That Last

A jin can add a lot of character to a tree, but creating a jin can take a fair amount of time. To be more efficient, you should focus on working the heartwood, which is usually a lot tougher than the surrounding tissue.

Where Does Moss Belong

A tree can look wonderful with a nice carpet of moss, but moss can also starve a root system of water, air, and nutrients. So remove the moss except for when a tree is being prepared for show. The tree will be the healthier for it.

Soil Mix

Everybody has a favorite (or convenient) soil mix. The most important thing seems to be balanced moisture retention with porosity. For trees with fibrous roots, Rodney suggests a mix of Kiryu sand, lava rock, and pumice (thirds of each). Trees with more open root systems seem to like the mix as well, but with two parts Kiryu.

To be honest, I'd never heard of Kiryu before this particular Saturday. Rodney notes that its a good alternative to Akadama, so I plan to give it a try. Like most of us, I'm a soil mix junky.

One more thing... You can purchase Kiryu at the Monastery in 10 kilogram bags. It's actually on sale for $24 since the store ran out of Akadama. Look for Kiryusuna River Sand on the store's website.

Warren Hill at Steve Cratty's

In case anyone missed this announcement...

Also... Show of hands for group members who might make the trip to Asheville. I believe the event occurs the same weekend as our October meeting with Rodney.

Warren Hill Open Workshop
October 16, 2010

• Class times: 9am-12pm & 1:30pm – 4:30pm
• Lunch served at 12:30 for all participants
• Class Fee: $75 plus cost of tree
• Reserve your spot now!
• Phone: 770 983-3377
• Email: plantcitybonsai@gmail.com

We look forward to seeing you soon!! Steve and Sandi.
WHO is warren hill?
Well known Bonsai Master Instructor and former Supervisory Curator for the U.S. National Bonsai Collection. Warren majored in engineering and horticulture while attending college. Warren’s formal Bonsai studies and training has been with a wide variety of Japanese Sensei (teachers) which include such notables as John Yoshio Naka and Saburo Kato. Warren has conducted lectures, demonstrations and workshops for numerous State, National and International Bonsai organizations. He has authored numerous articles on Bonsai and Horticulture for State, National and International publications. In 1996 Warren was selected by the Federal Government, U.S.D.A., Agricultural Research Service, to be the Supervisory Curator for the United States Bonsai and Penjing Museum at the U.S. National Arboretum, Washington, D.C.

full season horticultural oils

The Sun Spray horticultural oil has been discontinued. We are still using it because we stocked up when we heard about it being discontinued. I called my supplier and asked for the name of an appropriate replacement. Prescription Treatment horticultural oil was recommended. Other companies make full season horticultural oil. Some options are: Summit, Bonide, Hy-Yield and Ferti-Lone. I don't care to use Volk oil spray because of the bad smell and that some trees don't take to it well. When I checked on application instructions, there was a range of 85 degrees to 90 degrees occurring within 48 hours when it should not be applied. So be safe, and don't apply over 80 degrees. There might be a horticultural oil called Wipe Out; I am only familiar with Wipe Out as a broad leaf weed killer.

Roundup

Round up -

Don't Borer Me

I walked out this morning and noticed that a branch on my bald cypress had died. I had noticed some oozing previously but didn't give it a lot of lot. I'm now thinking borers. Any other ideas?

Update: Bob Gilbert and Rodney both confirmed that the problem is borers. So far it looks like I'll only lose one branch. Rodney notes:


"I think you and your Bald Cypress will be fine since the borers were high up in the tree. Bald Cypress compartmentalize quite well and flood the borer tunnels with sap. It was Mother Natures way of playing Bonsai Artist ( and she's always has the final say). I agree with you on using the "nasties"---- that's why I push so hard on coming out of Winter bug free. What you can use for dormant tree spray are the safest chemicals to use."   Rodney


One of the "nasties" Rodney was referring to is a systemic called Lindane. It was removed from the market several years ago over concerns that it caused neurological damage (among other things).


Rodney advised that if I detected further activity, I should inject the borer holes with insecticide and then seal. I have removed the dead branch and cleaned the sap from the tree with alcohol and am now watching for additional damage. I've also ordered a horticultural syringe and needle just in case. 


Last tidbit...


Rodney advises that borers enter in January and that damage shows up in August (right on schedule). That's why it's best to dormant spray trees in winter and then treat with Bayer's Tree and Shrub in the spring.

Donation of Pratt trees to SGG

I thought you would like to see some snapshots of 34 trees that will be donated to SGG in October. The donors are Sid and Mary Pratt of Snellville. They used to be members of the local club. Sid began bonsai shortly after he came back from WWII (European Theater, MD). Susan and I will take inventory and history of the trees this Sunday.

Rick

Sharing Bonsai Nuggets

I thought we might all benefit from being able to post nuggets of information gleaned from our study group meetings. It's an experiment, of course, since I don't know how much interest there is in interacting online.

In any case, here are a few of my notes from the August 14 meeting. I recorded these suggestions as Rodney was circulating around the room working with individual members. (Please chime in if you see any misinformation or have a different take on a particular bonsai practice.)

October Pine Work

October is a good time to prune black and white pines for structure and to force latent buds to emerge on the interior of trees.

This month is also a good time to repot white pines. (I'm assuming we want to protect the tree from freezing for at least a couple of weeks after repotting.)

It's also a good time to pull third-year needles to allow light into the interior and encourage budding. Some second-year needles can be pulled as well if the tree is vigorous. When pulling needles, it's important to leave the sheath intact, as this is the point where a latent bud may emerge. If you don't know the technique for pulling needles without removing the sheath, you can cut the needles with pruning shears.

February Pine Work

February is a good time to wire pines. Trees will experience a spurt of growth in the spring that will promoting "setting." That is, the cambrium will press against the wire, rupture slightly (ideally), and then heal.

Pest and Disease Control

There are many chemicals for addressing various conditions, but Rodney seems to find lots of utility in using Sunspray Ultra Fine Horticultural Oil. It is particularly valuable as a pest control when used in November and again in February. Some care needs to be taken to avoid spraying trees when the weather is expected to freeze.

Oil can also be used to control Red Spider Mite by spraying trees 3 times x four days apart. It's important to maintain this treatment schedule to interrupt the Mite's life cycle.

You should not spray oil when the temperature is greater than 90 degrees. Leaf burn can result. It's also important to adjust the dilution rate for temperature.

Correction:
Spraying pines with Cleary's 3336 or copper once a month from April through October is also a good strategy for controlling needle caste.

I went online to order some Sunspray and found out it is no longer being manufactured. As a substitute, I've ordered a one quart bottle of Wipeout. If anyone has any reservations about this product, please let me know (before I spray).

Rotating Trees

Everyone understands that rotating trees during the growing season is a good thing. What most of us don't know is that trees benefit from rotation during dormancy as well. It a good idea to rotate your trees year round every two weeks.

Promoting Good Nebari

Wounding a tree at the base is sometimes suggested as a way to promote new root growth. Rodney suggests that it is actually better to remove an elliptical wedge of tissue. This larger wound prompts a more vigorous healing response and a better chance of root development. It's often desirable to make several of these wounds at once--although you want to avoid aligning them on the truck. Some variation in height is more natural.

Creating a Broom Style

I brought along a Zelkova that I was attempting to style into a broom. I had followed the instructions in Dan Barton's books but was not satisfied with how the tree was progressing.

Rodney noted that my cut was made too high up on the trunk. Branching on a broom usually starts at a point that is fairly low on the trunk in comparison to the ground. Rodney advised that I make a straight cut in early spring just above an obvious bud collar on the trunk. I should then wrap the cut in clear plastic and secure it with wire. After the tree budded, I could select the most promising initial branches to start the broom. At that point I could also make the off-center V cut that would let to give the tree a more natural appearance. (This last step was different from what Dan outlined in his book. With his process, the V cut is made at the same time as the straight cut. But I can see the value in waiting until after budding to make this decision.)