OK, first off let me say WillsC's stepover project is the inspiration for this.  This is still in the planning stage.  I'd like to hear thoughts/suggestions/ideas and incorporate them into the plan.

Goal: In ground stepover type figs with minimal/zero damage to horizontal growth, thereby enabling vigorous growth of verticals and sufficient time to ripen in zone 7a (Maryland).  Spring/Winter burying/unburying of trees should be as simple/easy as possible. 

Considerations:
1. Which varieties would be best?
2. How close should the horizontals be to the ground?
3. How far apart should the trees be?
4. How far apart should the verticals be?
5. How deep do they need to be buried?
6. Should each tree go one way or two?
7. What should be used to bury the trees?

Initial thoughts:
1. VdB, Hardy Chicago, Figo Preto, what else?  Looking for suggestions here.  Probably will do a 10 or 20 foot run, so that limits me to a handful of varieties.
2. As close as possible without actually touching the ground.  This allows for easy pruning while minimizing digging effort.
3. 3-6 feet?
4. 12 inches?
5. Depends on depth of frost line.  Probably around a foot or two here.  If I first dig a trench a couple feet wide, and a foot deep at the deepest point, then plant the trees there, I think I can maximize the thermal mass.  In other words, plant the trees below the normal soil line.  Then I will have a small mound instead of a large one in the winter. 
6. Maybe will do both.  Depends on what trees I end up using and whether they have two branches or one.  I have some trees that are more whip-shaped and might be ideal to just plant them leaning over severely and bend them the rest of the way.  If I use a newly grown cutting, would be more possible to branch it as WillsC did.
7. Thinking just regular topsoil is the best option here.  Has the most thermal mass.  So the mound in the winter turns into a V formation in the spring/summer after I dig it out.  Basically a trench with raised sides.  Then I can use landscape fabric to keep weeds at bay.

In our area, if you can do this against a south facing brick wall, data says you will have a better chance of being successful.
VdB, my Red Greek, any of the Brooklyn Italian or Greek figs would be my choices at the start.

When this is proven out then I would go for more boutique varities. My preferences are from the south of France.

You might find looking at this step over fig garden in Japan..
http://www.hawaiifruit.net/japanfigresearch/index.html

@James:
It's an interesting idea to slightly bury the horizontals to get them to root.  I think that is going to just be a different beast.  I might try one that way to compare.  But I have concerns about it.  Typically certain things flow up to the trunk/leaves, and certain things flow down to the roots.  If you get roots in the middle, won't that interrupt things and change the vigor of the shoots that are growing south of the roots?  Will it take longer to warm up and throw shoots, etc?  Let me know how yours work out and if you still get shoots all the way along the tree. 

@Gloria:
Thanks for the link.  I think I read that a couple years ago and it has been a bug in the back of my mind ever since.  Now I have a house and can actually give it a try.  I don't see any reason it wouldn't work on the east coast. 

Maybe I should use a hoop house in the early season to warm things up faster.  Would be easy to throw a hoop house over the horizontals until the shoots got too high. Maybe give them a couple weeks headstart. 

Rob, I was thinking you would want maybe 6-8 inches clearance between the ground the the horizontal trunks.  If they were in contact with the ground I think it would be more difficult to keep the suckers pruned off etc.  As far as varieties, given Wills' experience, you might not want to go with the most vigorous varieties but something with moderate vigor.  As far as covering it winter I was thinking shredded leaves along with a couple jars of mothballs with lids that have holes placed besides the horizontals to deter rodents.  Maybe mound up shredded leaves to cover the horizontal then some black plastic over that to keep it dry, and some sort of cover over the plastic like burlap or additional leaves to keep it from absorbing too much heat.

Rob,
1. Almost any relatively healthy cultivar can be used, preferably hardier cultivars in colder zones.
2. As close as you like.
3. As far apart as you want, but a good start is 10' on center, They can be thinned later.
4. The prescribed distance is 8" on alternate sides of the main cordon.
5. The normal depth, but since figs will produce roots on the main stem, "as deep as possible".
6. The prescribed is to train 2 horizontal branches (Cordons) in opposite directions.
7. Any material that will insulate the cordons and fruiting branch stubs.
Note the attached original Japanese Fig Espalier Info.

I posted my planned espalier in an earlier topic... http://figs4funforum.websitetoolbox.com/post?id=7063122

Quote:

The attached diagram has been modified to include the winterization plan that I'll be using this year with my in ground bushes and step over espaliers. The  scaffold branches (cordons) will be spaced approximately 2" off the ground and will be covered with Pine Shavings. This past winter all branches that were below the pine shavings survived the cold. The scaffold branches of the fig bushes will be cut back to just below the top of the mounds. Both bushes and Espaliers will be planted at ~ 3' below ground surface level.

Great question!  This is really interesting.  Thanks for the info Pete!

I am planning something similar for the side of my house.  I plan on using Chicago Hardy and Brown Turkey (no frowns please, lol).

/edit  I wish I knew Japanese to read the pdf!

Rob,

I'm really interested to hear how this progresses for you.  Are you planning on doing several rows of stepovers or just one continuous one?

The question of how to deal with the horizontals is perplexing.  If you did two going in opposite directions, you could have branches that intertwine eventually and grow together (such as what occurs when braiding).  The possible problem with this is if one of your trees comes down with some sort of catastrophic disease.  All trees that are braided together down the line in your stepover could be more susceptible to disease.

In terms of spacing the verticals I would give as much spacing as possible to promote good air circulation.

In terms of spacing the actual trees, you wouldn't want a scenario where they become stunted because of their roots are being crowded due to inter-twining.

I too would start off with some tried/true varieties that are known to be hardy, productive and tolerant to our zone to prevent die back scenarios as much as possible.

Speaking of die back, I would think die back occurring to the horizontal trunks would really set you back from a tree training perspective.  I would definitely recommend having your winter protection methodologies in mind when devising your system (i.e. being able to quickly erect a hoop house, etc. if the temperature plummets below what standard winter protection is capable of dealing with).

When are you planning on starting your stepover project?




 

Hi Malcolm

Unless life gets in the way, I'll start any cuttings and do any prep work this winter, then plant out this coming spring.  I don't have that much land (only about a third of an acre) so I will probably do one row along my property line.  One issue I have is that my soil is terrible.  The house is only 6 years old, and they removed any and all previous topsoil when they built it.  So I have this very rocky clay soil with very little organic matter.  I'd like to dig a trench and put in some better topsoil, but that will be a huge amount of manual labor, so we'll see if I get to it.  On the other hand, if I can get some stuff in there that is more workable, it will make future digging easier. 

I do plan on completely coverings the horizontal with a thick layer of soil and/or mulch.  If I bury them below the frost depth I can pretty much guarantee they will suffer zero damage from cold.  However, the frost depth varies from year to year, and I certainly don't want to put them any deeper than I have to, so the real question is, how deep is deep enough for most winters?  I am going to aim for about 1 foot and see how it goes.  That's a lot of digging, so we'll see how it goes.  I bet they could get a little colder than freezing and still be OK, but it's the potential for multiple freeze/thaw cycles that concerns me.   

I had considered using bales of straw and leaving them above ground.  Would love to use blocks of rice hulls like the Japanese, but I doubt it's available cheaply here.  But, I have some concerns with this hay bale approach:
1. probably would look like crap, disturb the wife (most important reason here)
2. probably would be a rodent haven
3. where would I put all that straw when not in use?  no room for large compost pile. 

Maybe you have more land where you are and could get a few dozen bales of hay cheaply.  Then you could stack those around the horizontals (1 on each side, snug against the branches, one or two on top).  Could put some moth balls in jars as rodent deterrent.  I bet that would provide enough insulation.  Could even do two layers if you wanted to almost guarantee no winter damage.  Even if you got a little rodent damage, I bet it would be a lot less than the damage winter can bestow.  And that system would be much less work than either digging or hauling pots in and out of your garage.  Bales of straw are light :)

Hi Rob,
As to rodents, ever seen a sharp pencil ? A really sharp pointy one ? That's how my first BT trunk ended ... The rodent came from under ground and it took me two months to figure out what had happened .
The poor BT eventually made a sprout but still died - supposedly the rodent attacked in winter through spring until I pulled the tree out.
Little damage from rodents ... Forget it ! I had to buy a new BT .
Rodents are a serious problem when it comes to fig trees . The wood on fig trees is so soft that they can chew it completely from bark to inner center .
Just my experience, hoping that our trees stay safe from rodents ...