Collection Decimated

Sadly, early this Spring I learned a costly and important lesson about bamboo. Over-watering coupled with poor drainage will indeed kill a bamboo pretty easily.  It seems I have lost at least 5 plants, all to root rot.  These include my S. Fastuosa, P. Nigra Othello, P. Aurea Holochrysa, P. Rubromarginata, and P. Kwangsiensis. My F. Robusta is barely hanging on.  Oh well, lesson learned. Better luck next time.  I did pick up two F. Rufa's and they are doing well thus far.

  

My Trip to Beautiful Bamboo in Groveland, FL

I was in Central Florida for a week in mid-March and I made a point of visiting Beautiful Bamboo, a Bamboo nursery in Groveland, a small community somewhat half-way between Orlando and Ocala.

The varieties they grow are generally tropical ones as you might guess, though they also carry an assortment of temperate running bamboos, including Phyllostachys bambusoides Madake, which I sadly didn't have time to view.


Below are some of the highlights.

This is a cool shot of the towering Bambusa Oldhamii - these must have been 40-50 feet tall.

Here's the same variety with my hand in the shot for scale - largest culms I saw were easily 4-5", though these are from a somewhat smaller stand.

Bambusa Chungii - a supposedly "blue" bamboo, though I found it more of a greenish-white.  I realize that most so-called blue bamboos are "blue" because of the white waxy film on the culms but this particular variety did not really come off as blue.  Still pretty unusual and interesting.

Bambusa Eutuldoides Viridi-Vittata - a relatively rare variety that seems to bear some similarity to Bambusa Multiplex 'Alphonse Karr', though with a more open clumping habitat, smaller leaves, and perhaps less of an open-vase shape.

Here is the Alphonse Karr for comparison:

One of the most unusual bamboos I have ever seen, here is the Bambusa vulgaris Wamin (Dwarf Buddha Belly).  The swollen nodes are very unusual, as is the branching.

A cool shot of a local hanging out on a Bambusa Lako culm:

Lastly, the new additions to my collection - I got a tiny Bambusa Oldhamii and a 3-gallon Alphonse Karr. Neither look very good right now, and may never look very good! I'm planning to grow both indoors under controlled conditions.

Update on my P. Kwangsiensis

In a previous post, I described how my P. Kwangsiensis looked like a goner.  It was completely defoliated and only about three or four thin culms looked even remotely green. 

Here it was when I first brought it indoors:

But then, about a week after bringing it inside, I started to see some small signs of hope:

 

Now, about a month later, there are definite signs of life.  There are  roughly 8 new shoots sprouting and there is also growth on two or three of the existing culms.  Apologies ahead of time, these pics were taken with my Blackberry.

Note the numerous new shoots:

Near the center of the image below is a new (out of focus) leaf growing on an existing culm.  My little moso seedling is in the background.

The re-birth of my P. Kwangsiensis is quite astonishing.  I was almost certain that it had perished.  I did fertilize with liquid kelp and I mist it daily - even though it had no leaves for the water to land on!

Update on my P. Rubromarginata - soaked leaves are not always healthy leaves

In my last post, I detailed how I had to dig up my Rubro in the middle of the coldest winter in 30 years and I discussed how well it seemed to have done.

I have now had a few days to observe it in my garage and it seems it is not as unscathed as I thought.  Here it is:

 

It seems I was fooled by leaves that had been drenched in water from thawing snow for a day or two.  Such leaves take on the appearance of healthy leaves but are in fact burned.  Still, the leaf burn appears to have affected only about 25% of the plant, which I would still call a success.  Surprisingly, my P. Aureosulcata 'spectabilis', which I failed to dig up, showed essentially 100% leaf burn, and I had protected it, though half-heartedly.

This soaked leaf phenomenon is something I think I first read on Alan Lorence's blog (can't seem to find the actual post).  Basically, leaves soaked in water seem to come back to life, but of course the effect is fleeting. 

Digging out a P. Rubromarginata in the middle of winter

Yesterday, after a 2 or 3 day thaw, I attempted to dig out a P. Rubromarginata, which was flattened and completely buried by snow cover.  I am moving homes and suffice it to say that I had no choice but to do this.  Below are some pics.


  Here it is after I dug out most of the 1-2 foot snow cover:

After clearing off the remaining snow, the garment bag that I used to protect the Rubro is visible.  It has a small opening in it, which made me think that something might have been nesting in it, and munching on it.

But then, the first good sign:

Then, a little more green...

And her it is - after a brutal winter that seems far from over...

Amazingly, the Rubro looks very, very good.  Bushy, healthy-looking, and NO leaf burn whatsoever! Here is a foliage close-up:

This is how I dug it out.  I connected my garden hose to my laundry faucet, which allowed me to soak the root mass with warm water. I then slowly, pain-stakingly dug it out.

Finally, success...

Well, sort of.  I did manage to dig it out but now, nearly two full days later, I see that it has experienced quite a bit of shock (no pic yet).  I have stored it in my garage because I don't want to bring it out of dormancy.

I left this Rubro for dead two years ago and to my surprise it came back very strong, so I hope it will hang in there for the next month or two so that I can get it into the ground.

I had planned to dig up another four plants but alas I failed.  The root masses were too large and the ice too thick.  I did manage to get two good chunks rhizome from my P. Aurosulcata 'Spectabilis' which I have potted indoors with the hope of propagate a seedling or two.

  

Winter Protection to the Extreme - Part II

The winter seems unrelenting this year.  Our snow banks are now 5-6 feet high!  As such, I have become inspired to write about some additional winter protection tools, some related to soil amendments/fertilizers and other more mechanical in nature.

1.  An Even Heavier Frost Blanket

I wrote in my last post about winter protection about the importance of tarping or otherwise covering marginally hardy bamboos.  I wrote about Dewitt, a company that produces a 3.0 oz frost blanket, they call their "Ultimate" line, that claims to provide as much as a 10F benefit vs. the ambient temperature.  Well, if 3.0 oz is "Ultimate", then 4.0 oz must be "Super-Ultimate" and 6.0 oz must be "Ultra-Ultimate". GinTec Shade Technologies offers just those.  They seem to be a wholesale/commercial distributor, but they may still sell to an individual.  Obviously, the benefit of a heavier blanket is not linear (6 oz is not twice as good as 3 oz), but even a gain of two or three degrees could make a difference to sensitive plants.


2. Seaweed/Kelp Applications to Roots and Foliage (experimental)

The verdict is still out on the use of seaweed/kelp on bamboo.  Seaweed/kelp has been show in a number of well-controlled studies as well as anecdotal accounts to improve frost tolerance, among other things.  It is commonly applied as a foliar spray but it is also likely beneficial as a soil amendment given its micronutrient profile.  Often, people will point out that seaweed/kelp is high in sodium given that is comes from the ocean.  Maybe, but let's run through the math.

The liquid kelp that I have begun using is from The Organic Gardner's Pantry, a retailer on the West Coast that will readily ship across Canada.  Included on the website is a chemical analysis of their product, which lists a sodium concentration of 2070mg/L.  Now, let's assume one gets a "salty" batch such that we will use 3000mg/L for our math.

Let's also assume that a sodium concentration of 40mg/L, an upper limit commonly used in many municipalities for tap water, is the upper tolerable limit for bamboo.  This is totally unscientific, but we are basically assuming that tap water in these municipalities does no harm to bamboo even when it is at its upper limit for sodium. Note that in Oakville and many other municipalities, mean sodium concentrations in tap water are actually closer to 15-25mg/L. 

At a recommended concentration of 1:250, the "salty batch" of liquid kelp would add about 12mg/L to one's kelp/water dilution, which in most cases would still keep the mixture below 40mg/L.   

Still concerned?  Switch or supplement with distilled water or rainwater (assuming you are not seaside).  You could also decrease the kelp concentration by 25%-50%.  Any of these measures would help keep your kelp/water mixture at a sodium concentration at or well-below the typical concentrations found in regular tap water. 

I can't yet speak to the efficacy of liquid kelp, but, though this is totally unscientific, it does seem to have given a boost to my very sickly P. Kwangsiensis.  It also seems to have benefited my P. Viviax, my P. Edulis Moso seedling, and my Semiarundinaria Fastuosa.


3. Low Nitrogen / High Potassium Fertilizer

Ample research [eg. here, here, and here] suggests that low nitrogen / high potassium fertilizer, applied late in the growing season improves cold tolerance among various grasses.  I have not found any research specific to bamboo, but since bamboo is in the grass family, we "might" be able to apply these finding to bamboo.


4. Planting location
 
This is a simple but important and effective winter protection method that I failed to mention in my last post.  There are often different micro-climates around a typical property.  For us in suburbia, we typically have several areas around the property that are fairly sheltered from cold, desiccating winds, and some areas that may actually stay slightly warmer than the ambient outside temperature, such as near a foundation or a furnace exhaust (but remember to keep a reasonable perimeter clear around your exhaust!).

Planting with a view to a particular exposure is debatable.  Southern exposure gets more sun/heat during the day but also results in greater temperature swings, which is not great for any plant.  If you have thoroughly insulated the ground and the plant, thereby moderating the temperature swings, southern exposure might be a good option for enhancing the winter protection of a marginally-hardy bamboo.

So there you have it.  I have no more tricks in my winter protection bag (yet).   
   
         

Glimmer of Hope for my P. Kwangsiensis

It is difficult for us in Ontario to get bamboo.  Few nurseries carry any, and few other local sources exist.  As such, I often have to get creative in sourcing new plants.  This past summer, I ordered three plants from Victoria Bamboo, a nursery some 4000+km's away.

Steve at Victoria Bamboo was very informative, helpful, and accommodating.  He was not too keen, however, on organizing cross-country shipping.  So instead I had Steve deliver the three plants to my friend who lives near his nursery.  She was more amenable to arranging the shipping (so I thought).

One of the plants I got from Steve was a P. Kwangsiensis.  Steve is likely the only retail source of this variety in Canada. When the plant arrived at my friend's house, it was in good shape, which she confirmed with iPhone pictures.  She promised to ship me the plants "by the end of the week".  Not quite.  Six weeks later, I got the plants.  She warned me, however, that one of them "looked like a goner".  When it arrived, the P. Kwangsiensis looked like it had been left to bake in the sun with no water for about...six weeks. It was about 75% defoliated, with a few culms already greyish yellow.

I thought to myself, this is too rare a variety to simply throw away. I decided to re-pot it using a compost and triple-mix blend. I then lightly fertilized it with a lawn fertilizer on two occasions before November.  It didn't perk up.  In fact, it looked like it was getting worse.  After moving it into the house recently (to protect it from the severe cold, even in the garage), it looked so bad that I had pretty much lost all hope for it:

I decided to make one last attempt at saving this bundle of sticks that used to be a beautiful, rare variety of bamboo. I started spraying it daily with a weak liquid kelp/distilled water mixture.

Today, after doing this for only about a week, I saw a few glimmers of hope.  The first, an emerging shoot, I had actually noticed soon after bringing the pot into the house:

Today, however, I also noticed two emerging leaves.  Here's one of them, emerging from a healthy-looking green culm:

The plant has a long way to go before it becomes "stable", but it looks like with a lot of care and a little luck it might get there.

Hardiness Zones

There are numerous resources out there that will determine your hardiness zone but the one I typically refer Canadians to is the Agriculture Canada online app.  As is typical of many of our government initiatives, it is somewhat clunky and inefficient, but it means well and actually provides very useful information.  This app will allow Canadians to zero-in on their city/region, and even their specific neighbourhood, to determine their hardiness zone, and it also allows users to toggle between the 2000 Hardiness Zone Map and the 1967 version.

It seems that the 1967 version suggests that many Canadians live in a slightly higher hardiness zone than the 2000 version.  The 2000 version, which is based on data collected between 1961 - 1990, seems to be somewhat skewed by particularly cold winters in the 70's and 80's. Organizations in the US such as the American Horticulture Society and the US National Arbor Day Foundation have found a similar phenomenon which eventually led to the USDA updating its map in 2012 to reflect generally warmer winters since 1990. Agriculture Canada has yet to update its map.

This is the reason I list my hardiness zone as 6a/6b.  It is exceedingly rare for Oakville to experience a low of -20C or colder, and in fact, the coldest winter lows seem to hover around -16C to -18C and remain there for only a few hours during the night. That would put Oakville in zone 6b, though still at risk of an extreme cold snap every 10-20 years, a la January 2014!.  Still, even this year, the air temp hit a low of -21C, which would just barely bump Oakville into zone 6a.

Winter Protection to the Extreme

Growing bamboo and other exotic plants in climates far removed from their native ones typically requires some "man-made" accommodation.  For those of us in zones 5, 6, and 7, this essentially means winter protection.  This absolutely brutal winter has inspired me to consider the most effective winter protection methods, even those that seem extreme.

First, an admission.  I was lazy this year and, relying on the string of mild winters we have had here in Southern Ontario, I thought I could get by with mediocre winter protection. In the spring, I think I will have found that I learned a costly lesson.  So, never again.  From now on, winter protection will be a top priority!

Below are a number of different means of winter protection, some cheap, simple and easy to implement -  others not so much.

1. Use planters that you can move into protected environments during the coldest months

This is of course the simplest winter protection method and something I have done myself with a number of my plants. You need not be relegated to small pots.  Planters as big as 20, 30, and 40+ gallons can be moved with some equipment (e.g. a dolly, or wheels attached to the base of the planter).  This allows you to grow relatively climate-sensitive specimens that can actually achieve quite a large size.  I have seen 14'+ bamboo in large custom planters.  Of course, finding a winter home for such plants and planters may prove a bit of a challenge.  A well-insulated greenhouse with some added propane/gas heating would be the "gold standard" for over-wintering such plants.

2. Mulch

Mulch is the mainstay of any winter protection program for plants that remain in the ground.  Mulch basically helps the soil, and hence the roots and rhizomes of a plant, retain heat and moderate temperature drops.  It does this by better absorbing solar radiation than bare soil (or snow for that matter) and by insulating the soil. For example, although the day's high may only be -8C, to many bamboo that compares very favourably with a low of say -18C.  Mulch will help the soil spend more time at -8C (or higher because of its absorption of solar radiation) and less or no time at -18C.

People tend to be very loyal to the mulch they use, and there is no single perfect mulch out there; however, when considering ONLY winter protection, Straw has the best insulation capacity.  This is also why rodents like to nest in it.  Straw also tends to rot easily.  I have read that applying straw in early winter, after a solid frost (mid/late November for most of us in Southern Ontario), helps prevent rot and rodent infestation.  While one could leave the straw in their planting beds in the spring, I would rather remove it and dispose of it.

Another admission.  I have yet to use straw. I typically mulch with 6-8"+ of a pine mulch and shredded leaf combination.  The insulation is relatively good and I don't have to pick it up in the Spring.  I would use straw on zone 8 bamboos, on bananas, and on palms (but I don't have any of those yet!).             

3. Tarps, Blankets, Coverings of Some Kind

Depending on the hardiness of the varieties grown, covering bamboo with some sort of tarp, blanket or thick poly sheet may be necessary. 

This year, I used a cheap clear plastic sheet on my P. Spectabilis and I am sure I will pay the price for it. For most plants, I would use a 3 to 5 mil poly sheet, or as it is know in agricultural circles, "overwintering film".

If you are growing a marginal bamboo for your climate, I would instead invest in a high-quality frost blanket. Why go to all the effort of growing an exotic plant and not invest in protecting it? DeWitt is a popular manufacturer of frost blankets which come in weights of up to 3.0 oz..  The 3.0 oz "Ultimate" blanket claims "up to 10 degrees (F) of frost protection" compared to the ambient temperature.  Expensive? Sure.  Extreme? Somewhat. Worth it for a plant that you have spent two or three years nursing and that would be difficult to replace? Absolutely. 

This year, I also used a tent-like woven poly frost blanket for my F. Scabrida.  These are great as they are easy to set up and use, but the largest of these particular tents that I have seen seems to be about 4 feet high.  I suppose one could perhaps bend over a 7 or 8 foot tall bamboo and cram it in there, but obviously, plants taller than about 8 feet and wider than about 3 feet will not fit in these tents.

Custom build structures using chicken wire and filled with some insulating material are also typically very effective.  See this post on Steve Lau's blog for an example.

On a final note, I have read that light transmission is probably not important for bamboos during the winter as they remain dormant and do not photosynthesize sunlight.  This is why bamboo covered in snow for three months typically looks ok in the spring.

4. Chemical Treatments    

Now we are really entering the realm of extreme winter protection.  There are two chemical treatments that one could use to help overwinter bamboo and other plants.  These are both "anti-dessicants' but one is meant for leaves and the other for roots.  These essentially help a plant hold onto its moisture and prevent dessication by coating the leaves and roots with a waxy yet bio-degradable film. Wilt Pruf is the most popular anti-dessicant for leaves.  Root Zone is an anti-dessicant (or anti-transpirant if you prefer) for the roots of a plant.    

5. Radiant Heating (experimental)

So you've mulched, tarped, used anti-dessicants, and you are still worried.  Well then you probably shouldn't be growing what you are trying to grow in the climate zone you're trying to grow it!! But let's assume you love the challenge and damn it, you want the yard of your cottage in the Muskokas (zone 5a/b) to look like Tahiti. Ok, there is one last extreme winter protection method I can suggest - though it is experimental and I have never tried it.

Basically, the idea involves the use of outdoor spotlights or "brooder lights" fitted with infrared heat lamps.  Typically, these light fixtures can support anywhere from 150W to 300W bulbs.  175W and 250W infrared bulbs are fairly widely available.  During extremely cold periods, one could conceivably aim one or more lights at a plant.  Because the heat is of the radiant type, the plants would be heated so long as they were exposed to the light.

There are a number of issues with this idea.  Some of these are:

       1.  Cost and Complexity - obviously difficult and expensive to set up and operate
       2.  Heat Damage - if the lamps are placed too close to the plant, if they blow onto the plant, or if they are simply too powerful, heat damage is a risk. Fire is also a risk.
       3. Complaints - Neighbours may not take too well to a bank of red lights glowing in your yard throughout the night, though if you want to get really extreme, you could avoid this by getting ceramic dull emitter infrared bulbs, which emit no visible light, only infrared light.

If you have tried all of the above and your plant still dies from cold-related injury, then you may be trying to grow an tropical Orchid outdoors in Winnipeg. I can't help you!

Runners more cold-hardy than clumpers

I came across this interesting abstract that essentially seems to conclude that runners (monopodial rhizomes) are more cold-tolerant than clumpers (sympodial rhizomes) by looking at snow and ice damage during a particularly treacherous winter in China.  This is consistent with the experience of those at Needmore Bamboo. They don't seem to have had much luck with Fargesia's in Zone 5b.

I have had pretty good performance from my F. Scabrida in zone 6a/b, and my new F. Robusta seemed to do fairly well early in the winter before I moved it into the garage, but I think planting location, fertilizer, mulch, and winter protection have a lot to do with my modest success.

Maui Ocean Center - Bambusa Vulgaris Vittata

Saw an interesting variety recently on a trip to Maui.  Thanks to Steve L. for identifying it as Bambusa Vulgaris Vittata ("Golden Painted Hawaiian Bamboo"):

I originally thought it might be P. Vivax Huangwenzhu Inversa given the unique coloration of the culms.

I do know that this is one variety that will not tolerate zone 5, 6, or likely even 7. Those few Canadians in a solid zone 8 might have a fair shot with this variety, though it would still likely require some winter protection.  This basically means residents of the lower-lying coastal regions of Greater Vancouver and the lower-lying, southern part of Vancouver Island (and most of the little islands in between).

-34C With the Windchill - Brutally Cold!

Today, the air temp hit a low of -21C, -34C with the windchill - not exactly bamboo-friendly weather.  This winter has been BRUTAL! Absolutely the coldest I have experienced in my 7 years in Southern Ontario.

I have five plants in the ground right now.  Three others I managed to pot and bring into the garage before the really bad cold hit.  Since then, the garage has become so cold that I took a number of my more sensitive plants indoors.  This means they have come out of dormancy, which will be tricky to deal with.

Of the ones in the ground, here's a re-cap:

1. P. Aureosulcata 'spectabilis' - Mulched heavily with pine chips and leaves, but I could have done better protecting it - just a plastic trap wrapped and taped around it.  Leaf burn is pretty bad.  I learned my lesson this year.  Will cover it better next year if it survives. Here it is pre-winter:

Here it is now:

2. P. Rubromarginata - Mulched heavily with pine chips and leaves.  Covered with one of those thick plastic garment bags, which I managed to zip up almost fully.  It is buried under a foot of snow so I have no idea what is going on under there.  Here it is pre-winter:

3. F. Scabrida - Mulched heavily with pine chips and covered with one of those tent-like frost covers.  Can't get a good look at the leaves but looks like leaf burn has set in. Here it is pre-winter:

Not much to see now:

4. P. Parvifolia - Mulched heavily but left unprotected. This one was weak going into the winter as it was a plant that I brought in from a friend in Rochester, NY.  Since you're not allowed to bring soil across the border, this went about 6 hours essentially bare root, though the roots were wrapped in wet newspaper and bound with plastic wrap. One of the culms died off early on.  The other was hanging by a thread.  My only hope is that the root ball is viable.  Here's a pic of it during the recent ice storm:

5. P. Atrovarginata - Mulched heavily but this one was also from Rochester and also very weak going into the winter.  It essentially died to the ground before winter hit.  Low expectations for this one. No photo because it's just a dead culm sticking out the ground.

Fortunately, I managed to pot and move many others into more protected environments.  These are in my garage, where it still gets down to about -7C on the coldest nights:

 F. Robusta

 P. Nigra 'Othello'

 P. Aurea "Holochrysa':

These I moved into the house:

a small P. Parvifolia (pretty sad looking but it's been surprisingly stable for several months - hope it perks up)

P vivax huangwenzhu inversa (now bursting with new leaves - only one week after bringing it indoors)

P. edulis 'moso' (just a small seedling - note three tiny shoots emerging again only one week after bringing it indoors)

P. kwangsiensis (has been in very bad shape basically since I got it - I do see one tiny new shoot)

Semiarundinaria Fastuosa

Indocalamus Tessellatus

Pleioblastus viridistriatus (?) - this one I left for dead but to my surprise it is slowly coming back. Stunning yellow/lime coloration

Pseudosasa owatarii (?)

another ground cover bamboo I haven't been able to identify (any help would be appreciated)

So there you have it.  My complete collection thus far.  I aim to add 3-4 plants this spring, perhaps more, depending on how many I lose this winter.