Growing Potatoes Above Ground in a Lehigh Bin
Q. Bruce in Toronto writes: “I’m planning on making a ‘Lehigh bin’ for my potatoes next year, but I can find no reference as to how large the gaps that the potato greenery will grow through should be between slats. I want enough room for the potato plants to be able to come out sideways, but I don’t want to be losing soil because the gaps are too large. Could you please make a suggestion?”
A. Absitevely, Bruce!
First, let’s explain how a classic Lehigh bin is constructed. You get enough slats of four-foot-long rot-resistant lumber to make a bin that’s four feet high and wide: 4 x 4 x 4. But you don’t build solid walls. Instead, you stack each piece of lumber so that you have a slat, then an opening the same size as the slat, then another slat, then another opening, another slat, on and on until you reach four feet high, although there’s no harm in going higher.
I called master craftsman Fred Matlack to help me better communicate the look of this structure, and he replied that the design is the same as the classic “log cabin corner lap”. Way back when, he relates, log cabins were built by layering logs in this same manner; “then the gaps between the logs were packed with wood chips and clay and plastered over.” (Which you will not do.)
Fred continues: “Someone with even rudimentary carpentry skills should be able to build a Lehigh Bin. I recommend they use two by fours for the lumber. Just be aware that {quote} ‘two by four’ is an archaic and technically inaccurate term that refers to the initial cut of the lumber, which was two inches by four inches when fresh cut. But the wood then shrank during the drying process and the result was inconsistent, so lumber mills established a new standard, shaving the dry wood to make it a consistent inch and a half by three and a half. (Although everybody still calls it a ‘two by four’.)
“When these ‘two by fours’ are stacked to make the classic Lehigh bin, the openings between the slats will be three and a half inches, which is just about the width of the four fingers on one hand. Cedar is the more expensive choice of wood, but it will last longer. Dirt cheap untreated pine should last for several seasons; a few more if you don’t mind the bottom boards showing some signs of decay.
And if you’re only using the bin to grow potatoes, you can empty it out, fold it up and store it inside in the off-season for an even longer life.
“The finishing touch is to drill matching holes on all four corners and inserting a metal rod down the entire length of the lumber to hold the bin together. Use a fiberglass rod if rust is an issue.”
Thank you, Fred. Fred Matlack is an amazingly talented carpenter who built my office furniture using boards from an old barn, built our laundry room cabinets out of old packing crates and built all the structures for ORGANIC GARDENING’s award-winning major exhibits at the Philadelphia Flower Show in the nineties. He is also an excellent singer and can disarm a nuclear device using three paper clips and a stick of Juicy Fruit gum.
Back to Bruce in Toronto. I don’t believe the spacing between the slats will be an issue. Remember, these bins (designed by engineers at Lehigh University and the legendary J. I. Rodale, the man who coined the term “organic gardening”) were originally designed as compost bins, and I can personally assure you that they hold their contents well. If a little dirt (or compost) does spill out, just scoop it up and toss it back on top.
Shovel a mix of screened topsoil, perlite and compost into the empty bin until it’s about a third full. Then place one seed potato in each quadrant (North, South, East and West). Position them close to the outside, with the biggest eye facing out. Then fill the bin up another third and repeat. When you get about halfway between the top of the previous batch of soil and the top of the bin, place a third run of seed potatoes on each quadrant and one spud in the center.
Be sure to bury this final run under enough soil that the developing potatoes won’t be exposed to sunlight. The green leaves that emerge through the slats and top should get as much sun as possible, but the new potatoes should never be exposed to the sun, or they’ll turn green; a sure sign that toxins have developed.
Water the bin deeply and water again anytime you go a week without an inch of rain. At the end of the season, just lift the bin straight up and go treasure hunting; if the soil was loose enough, you should get around five pounds of potatoes for every seed potato you planted—without any digging!
One final word of advice: Don’t ‘coin’ your seed potatoes. Cutting them into pieces is something commercial farmers pretty much have to do to keep expenses down. But it greatly increases the risk of rot, especially if Spring is cool and wet.
A. Absitevely, Bruce!
First, let’s explain how a classic Lehigh bin is constructed. You get enough slats of four-foot-long rot-resistant lumber to make a bin that’s four feet high and wide: 4 x 4 x 4. But you don’t build solid walls. Instead, you stack each piece of lumber so that you have a slat, then an opening the same size as the slat, then another slat, then another opening, another slat, on and on until you reach four feet high, although there’s no harm in going higher.
I called master craftsman Fred Matlack to help me better communicate the look of this structure, and he replied that the design is the same as the classic “log cabin corner lap”. Way back when, he relates, log cabins were built by layering logs in this same manner; “then the gaps between the logs were packed with wood chips and clay and plastered over.” (Which you will not do.)
Fred continues: “Someone with even rudimentary carpentry skills should be able to build a Lehigh Bin. I recommend they use two by fours for the lumber. Just be aware that {quote} ‘two by four’ is an archaic and technically inaccurate term that refers to the initial cut of the lumber, which was two inches by four inches when fresh cut. But the wood then shrank during the drying process and the result was inconsistent, so lumber mills established a new standard, shaving the dry wood to make it a consistent inch and a half by three and a half. (Although everybody still calls it a ‘two by four’.)
“When these ‘two by fours’ are stacked to make the classic Lehigh bin, the openings between the slats will be three and a half inches, which is just about the width of the four fingers on one hand. Cedar is the more expensive choice of wood, but it will last longer. Dirt cheap untreated pine should last for several seasons; a few more if you don’t mind the bottom boards showing some signs of decay.
And if you’re only using the bin to grow potatoes, you can empty it out, fold it up and store it inside in the off-season for an even longer life.
“The finishing touch is to drill matching holes on all four corners and inserting a metal rod down the entire length of the lumber to hold the bin together. Use a fiberglass rod if rust is an issue.”
Thank you, Fred. Fred Matlack is an amazingly talented carpenter who built my office furniture using boards from an old barn, built our laundry room cabinets out of old packing crates and built all the structures for ORGANIC GARDENING’s award-winning major exhibits at the Philadelphia Flower Show in the nineties. He is also an excellent singer and can disarm a nuclear device using three paper clips and a stick of Juicy Fruit gum.
Back to Bruce in Toronto. I don’t believe the spacing between the slats will be an issue. Remember, these bins (designed by engineers at Lehigh University and the legendary J. I. Rodale, the man who coined the term “organic gardening”) were originally designed as compost bins, and I can personally assure you that they hold their contents well. If a little dirt (or compost) does spill out, just scoop it up and toss it back on top.
Shovel a mix of screened topsoil, perlite and compost into the empty bin until it’s about a third full. Then place one seed potato in each quadrant (North, South, East and West). Position them close to the outside, with the biggest eye facing out. Then fill the bin up another third and repeat. When you get about halfway between the top of the previous batch of soil and the top of the bin, place a third run of seed potatoes on each quadrant and one spud in the center.
Be sure to bury this final run under enough soil that the developing potatoes won’t be exposed to sunlight. The green leaves that emerge through the slats and top should get as much sun as possible, but the new potatoes should never be exposed to the sun, or they’ll turn green; a sure sign that toxins have developed.
Water the bin deeply and water again anytime you go a week without an inch of rain. At the end of the season, just lift the bin straight up and go treasure hunting; if the soil was loose enough, you should get around five pounds of potatoes for every seed potato you planted—without any digging!
One final word of advice: Don’t ‘coin’ your seed potatoes. Cutting them into pieces is something commercial farmers pretty much have to do to keep expenses down. But it greatly increases the risk of rot, especially if Spring is cool and wet.