Overseeding pastures

The thought of seeding pastures may seem preposterous – after all, grass just grows! But for stressed or overgrazed pastures, overseeding may be just what the doctor ordered.

Bare pastures are probably all too familiar to many horse owners, especially those who keep their horses at boarding barns where it’s considered more feasible to stretch the available pasture space to contain as many horses as possible. In these situations, the pastures suffer. Luckily, there are many ways to prevent these things from happening, including pasture rotation, use of a Paddock Paradise, and overseeding.

The negative effects of overgrazing

Overuse of pastures has many negative effects that become increasingly obvious over time. These include:

  • Diminished grazing for your horses. This leaves you with bored horses that are not grazing constantly as nature intended; or with the need to supplement with hay, an added effort and expense.
  • Overgrowth of opportunistic weeds.
  • Erosion due to lack of ground cover.
  • Increased runoff into surrounding water sources, and potential for contamination.
  • Stressed, overgrazed grasses increase your horse’s risk of laminitis, due to a higher sugar to fiber ratio.

Overseeding your pastures

I was shocked when I first moved to a facility where the owner overseeded the pastures. The grass was already there – what would overseeding do? Grass just grows, doesn’t it? Why would you need to plant it?

We started off by cutting back weed growth and harrowing the fields to break up the manure. Using a small seed drill (you can also use a broadcast seeder, but it is more effective to get the seeds ¼” to ½” into the soil), the pastures were covered with a mixed grass seed. What you plant and when you plant it will depend on your location, soil type, and seasons – if you contact your local agriculture extension office they can often offer tips and guidance. It is also suggested that you test your soil prior to seeding to determine pH levels and nutrient content. There is no point in planting if your soil is poor. The information provided by soil testing will allow you to amend your pastures with fertilizer and/or lime as needed.

The most difficult part after seeding was keeping the horses off the pasture until the new grass had an opportunity to become established. We created sacrifice areas to keep the horses in until the fields were ready. While general advice is to keep horses off the fields for six to eight months after overseeding, this is not a possibility for us, so we overseed yearly and make sure each pasture gets a rest for at least a few months. Many people will opt to overseed and rest half their pastures one year, and do the other half next year, so they always have use of pasture space.

The results have spoken for themselves. Our horses have adequate grazing from spring until the snow flies. While we do have some bare areas around gates and troughs, they are minimal and our horses are not standing around in mud, even when we have heavy rains. We get some unwanted weeds growing around fencelines, but rarely inside the pastures. Runoff during spring melt or heavy rain is minimal, and our fields are able to absorb moisture quickly. Most importantly, we are lessening our negative impact on the environment.

Top tips for overseeding

  • Contact your local Ag extension office for assistance on the best type of grass/mix for your pasture, and the best time of year to plant for your area.
  • Remove weeds from the pasture before you start.
  • Harrow the pasture to break up manure, old hay piles, etc. (Bonus points for finding lost shoes, fly masks and halters!)
  • Test your soil to determine pH and nutrient levels. Balance your soil as needed with fertilizer and/or lime.
  • Use a method (i.e. seed drill) that will place the seeds into the soil at a depth of approximately ¼” to ½”.
  • Be sure to keep horses off the pastures until the new grass has time to establish itself. Turning your horses out too soon will undo all your hard work. Creating sacrifice areas will allow you to still turn your horses out while keeping them off the pastures.
  • Rotate and rest your pastures, if possible, so there is less stress on them in the future.