Building a Garden Bench

in DIY
Tags: bench, DIY, gardening

Gardening has pretty much wound down for the year, but I can’t stop looking for things to do that bring me outside and into the garden. My most recent venture was to build and install a bench in the garden – a good off-season task.

Last summer I was driving down the road and slowed as I passed a yard sale. I spotted a large piece of white marble, so I pulled over and went to investigate. The marble was about 5 feet long, 14 inches wide and about one and a half inches thick. I like all kinds of stone so I bought it (for $10) – even though I wasn’t quite sure what I would do with it. It spent the rest of the summer leaning against a tree in my yard.

I decided that I would like to use the stone as the top to a bench. I knew full well that stone is not fun to sit on for a long time, but that a piece of marble would be a great visual draw – it would be visible from a long distance and it would encourage visitors to the garden to wander that way. I found a spot near a part of my brook that burbles loudly, and that is near a large “umbrella plant” (Darmera peltata) that is planted over some of my late sister’s ashes. It’s a nice place to sit and contemplate.

While in France this fall I saw a number of stone benches, and in each case the top stone was supported by other stones. But I couldn’t find stones that were the right size to create a stable base for the top, so I decided to use logs instead.

Using railroad ties or pressure-treated wood would have been a long-lasting and easy solution, but I didn’t want their chemicals leaching into the soil or my brook. Ideally I would have found some 10 inch diameter logs of cedar or locust, both of which will resist rot well, but none were to be found. What I did have was a native cherry tree that had been blown over last winter and was still waiting to be cut up. I cut several pieces to 22 inch lengths and selected two that had good straight cuts.

Rot occurs first in wooden posts right below the surface of the bark. I’ve found that even cedar fence posts last longer if skinned before putting them in the soil, and that the splash zone – the first 6 inches or so – also rot before the rest of the post. So I used a 2-handled draw shave (a carpenter’s tool for removing wood) and took off most off the bark. I like the look of the bark, so I left some on the upper part of each support post.

After peeling the logs I painted each with boiled linseed oil (that I use on tool handles) to repel moisture. I found that the ends of the logs sucked up lots of oil fast, but that the sides were less receptive. I gave everything 3 coats of oil. I used environmentally friendly, natural oil rather than a chemical.

I had purchased some 8-inch long spikes for the project, and drove 3 spikes into each log near the base of the logs – I measured up 3 inches, and drove them in about 3 inches with a sledge hammer. The spikes stuck out like rays, and serve to add stability and make each log more difficult to tip over once in the hole and covered with rocks.

I measured my dining room chairs, and saw that the seats are about 16 inches off the ground. I decided to make this seat a little lower – about 14 inches. Given the thickness of the marble, that meant having 12 inches of post above the soil surface – allowing me to bury 10 inches of each post. It’s important that this piece of marble (which weighs 100 pounds or so) not fall over.

I decided to place the two support posts 20 inches apart for maximum stability. I put steel rods in the ground to mark the locations, and used my shovel to create a 2-foot diameter circle around each rod. After removing the sod I dug down about 18 inches, then added 4 inches of crushed stone in the bottom for drainage, and an inch or two of sand on top of that. The sand made it so that I could more easily adjust the depth or angle of the two support posts.

I used a 4-foot carpenter’s level and a five-inch wide plank to make sure the two supports were set so that the top would be level. Then I filled the hole with rocks roughly the size of a loaf of bread and added more gravel and sand to fill in around them. Finally, I carefully set the marble top on the posts. It is stable, and the good drainage means it should last several years.

It was a chilly day but I treated myself to a cold beverage and sat down to contemplate my success and admire my Merrill magnolia tree. The magnolia is about 25 feet away from the bench and covered with furry buds that will burst forth in late April with lovely white blossoms. And then along came Sam the cat, who proceeded to sit down and give the bench his paw of approval.

Henry Homeyer can be contacted at henry.homeyer@comcast.net or P.O. Box 364, Cornish Flat, NH 03746