Selecting and Spacing Fence Posts
Fence posts are a major component of your fence and account for a large part of its cost. Reasonable alternatives are trees, wooden posts, and various sorts of metal posts. Irrespective of the posts (or trees) used, the maximum distance between them should be 20 feet for polypropylene fencing (all types of poly) and 15 feet for metal hexagrid fencing. If you are in an area where heavy snow loads are likely, shorten the distance to 10 feet.
Trees as Fence Posts: If you have them available, trees make ideal deer fence posts for both polypropylene and metal hexagrid fencing. Not only is a tree strongly anchored, but it looks perfectly natural; and since Nature abhors a straight line, a deer fence zig-zagging slightly from tree to tree in dappled shade tends to look very natural and to fade into the background even more than it would if it were running straight.
Wooden Posts: Another option is wooden fence posts (pressure-treated 4 x 4s or 5-6-inch rounds). These should be installed 3 feet deep (4 feet deep at corners, gates, and ends) or below the frost line if that is deeper. Wooden posts are generally about the same price or a bit less than comparable metal deer fence posts. However, they are more visible than the metal posts, expensive and cumbersome to ship, and costly to install.
Metal Deer Fence Posts: We offer three types of metal posts for polypropylene and metal hexagrid deer fencing: angle-iron posts with a black powder-coat finish, black pvc-coated round steel posts with caps, and black pvc-coated round steel posts with drive sleeves and caps. Unlike most of our products, these posts do not ship free if ordered by themselves in small numbers. The 10-footers are especially costly ordered this way because they must be shipped by common carrier.
Angle-iron deer fence posts: These come in 8, 9, and 10-foot lengths and cost less than the round posts. They look well in woodsy, farm, or garden settings. Use the 10-footers where your soil is loose and you want the post to grip the ground well, and 9-footers for all other 7-foot fence applications.
All the angle-iron posts come with a black powder-coat finish but are not galvanized underneath. Below ground they will last for 20 years, but above ground they need a little attention. That’s because the powder-coat finish can get chipped or scratched, and if this happens the post can rust out at the open place in as little as two or three years, depending on your climate. To prevent this, take a few minutes once a year to spray any rust spots with a puff of black rust-proofing paint.
Round black steel posts: Our 17-gauge powder-coated 1-5/8 inch round steel deer fence posts with caps are galvanized under their black finish, so they are maintenance-free and will not rust. They are also stronger than the angle-iron posts, hold the ground better, and look better in a residential or estate setting. We offer two different types: standard 9 or 10-footers and similar posts with 2.5-foot drive sleeves.
Standard round deer fence posts: Regarding the 9 and 10-footers, plan on putting the 9-footers at least 2 feet into the ground. Use the 10-footers to get a better grip on loose soil and also to get below the frost line in areas with heavy clay soil, so as to avoid frost heaves.
Round deer fence posts with drive sleeves: These can make installation easier. That’s because you can install the 2.5-foot sleeves at ground level instead of going up a couple of steps with a manual post driver. However, rocky soil can make insertion of the sleeves difficult (they tend to get tilted going in); and in that case you are better off using the standard round posts without sleeves so that you can see and correct the tilting.
Brace bands: Be sure to get brace bands for any round metal posts that you select. These bands prevent the fencing from sliding down the posts by providing an anchor point for a zip-lock tie at the top of the fence. The general rule is to have one brace band per post, but this does not have to be rigidly observed. (A few posts without brace bands will make no difference.)
Reference: Suwak, M. DIY Guide: How to Install a Deer Fence to Keep Wildlife Out of the Garden. Gardener’s Path, 2018. https://gardenerspath.com/how-to/animals-and-wildlife/deer-fence-diy/