When to mow thin pasture

I bought my property last Spring, and the 8 acres of pasture spent the Spring and Summer growing weeds that were often 6-10 feet tall. Then in September 2015, I gained access to a brush hog and mowed it all down. It's now grass and weeds that look like nice forage from afar, but really it's very thin when you walk through it.

I have a small flock of sheep on their now, but they won't keep up with the Spring growth, so I know I'll need to mow. In fact, already I could go mow it down closer to 3-4 inches if I wanted to, since some of it is up to 6 or 7 inches already. But should I?

I was thinking that I'd mow the back half of the field in early Spring to start clean with 3" grass, then let it grow and self seed in the summer before cutting it again. I probably won't let the sheep back in that area this year, since they will struggle to even keep up with the front half of the grass/weeds in my pasture. But is this a good idea, or is there a better way to thicken my pasture grass, besides buying and spreading seed.

I wasn't planning on seeding this year, until I learn more about whether I need to, and what grasses I would even want to seed after I get my soil tests. Mostly I 'm just wondering about optimal mowing timing.

Thin grass will not thicken just by mowing, especially if there are weeds growing faster than the grass plants.

I would section off the pasture so that you can use rotational grazing with the sheep first so that they have the ability to graze down specific areas, this will result in less mowing being needed as well as bringing more fertilizer from the sheep to specific areas.

The next thing to do is seed with fescues and perhaps Bermuda grasses, this will fill in the spaces in the thin pastures and result in fewer weeds being able to grow. The rotation through paddocks will allow the seedlings to grow both before they are grazed and then post grazing.
We raise hogs and we move them on a weekly schedule which allows the grazed pasture to recover since they don't get back on that paddock for a minimum of 12 weeks. The rotation schedule allows us to not have to mow any of the paddocks since each area has been sized for one weeks worth of grazing to bring it all down for regrowth. We also grow brassicas and other fodder plants along with the grasses for a varied palate pleasing mix for the hogs, this too helps with paddock management and the health of our hogs by providing higher protein than a simple grass pasture can provide.

For a mowing schedule, you would want to cut sections of pasture on a weekly rotation just as if you were moving the sheep around, this allows recovery and would get you into the rhythm of rotational grazing, which is what many are now using since it works very well for both the health of the pasture and the animals.

Thanks Bryant. I should have been more clear: I do have rotational grazing set up. But with just two bred ewes and a ram, I can't keep up with 7+ acres of pasture. This is why I thought it would be best this year to just have them use the front half, while I kept the back half mowed to emulate grazing (but without the natural fertilizer that the sheep offer). I'll be adding more sheep as I go, and then I'll begin using more of the pasture space. Do you think it would be better to just use all of the space now, and mow when they leave each paddock since they won't eat all the grass in a week? If so, I'd probably still leave one paddock clear so I can scythe and save hay for winter.

Also, you mention that your pigs are on a 12 week rotation. But from what I've read it's best to graze every 20 days in the Spring, and up to every 40+ days in Autumn when grass is growing slower (these numbers are for my climate and soil, of course). This optimizes the grass to be in that sweet spot of 3-7", where the leaves can maximize growth via photosynthesis. But if you're on a 12 week schedule, wouldn't you be growing well beyond that sweet spot? I'm not saying you're doing it wrong because I'm just a newbie to this, but I want to understand it better.

Thanks!

Our pasture paddocks are partial shaded and with the different plants we have growing (rape, seven top turnip, kale, mustard, collard, tall fescue, Bermuda, clumping fescue, field peas etc.) it takes a while for full recovery.
We have found that the use of small paddocks (around 1/3 acre each) works well with our current schedule, allowing good recovery of all the pasture plants before being munched down again.
It also allows the manure to become incorporated into the soil so we don't have to worry so much with parasites or other nasty things that can happen.
When fall comes, we usually have a few paddocks that can be cut for hay with my scythe.

We first tried using several large paddocks (1 acre) but found that it didn't do well for our pasture plants or the hogs, they tended to root much more than they do now.
As well as they didn't eat the whole pasture area down but selected certain spots that they took down to bare soil and then rooted that into mud patches.

It takes one of our current paddocks about 3 weeks to start regrowth because of the amount of shade we keep for the hogs.
The shade is for them to be able to get out of the sun and by the time we are back on that paddock the plants are still at optimal growth (grasses are up at 6.5 to seven inches and the broad leafed plants are around 10 inches leaf length.
It took us one full year to find the cycling that worked for both the plants and our animals.

We breed American Guinea Hogs and while we could reduce the sequencing through, when the babies come we don't move the sow and brood along with the others.
We have 12 of these small paddocks and since we have two broods a year from each sow there are times that we have three paddocks being used by a sow and piglets, we like to separate a sow and her brood up until they are on their own.
We don't sell a shoat or gilt until they are at least 14 weeks old, which gives us "mob" grazing ability for a few weeks each breeding cycle.

In your case, I would mow the paddocks as if they were being cycled through, that way you can cut and let the hay dry for bailing or stacking and keep good quality.
By doing your mowing in cycles, it will help the plants adjust to the schedule they will be going through as you add animals to your herd.
This is a decent strategy for us that has worked pretty well so far.
We keep lots of records, hog records, pasture records, garden records, orchard records that all help with our research projects and they give us a good way to see what improvements work on our land.
The ones that are found to be not as we predicted are scrapped or changed and when we find something that works really well, we keep it.
But, we are always starting new research projects with plants, soil and animals.

Letting your pasture go to seed over summer gives you tons of free seed per hectare and introduces a heap of organic matter. The favoured plant species ought to persist longer if we let them seed rather than cutting them short every year.
Young grasses tend to grow into a thick sward rather quickly unless there's something else wrong.

The best way to improve a pasture is to mow it a lot.

Weeds grow up faster than grass, but they do not go to seed faster. Mowing kills the weeds and allows other plants to fill in. It does take time, but look at the grass seeding rates for pasture; it is only 30 pounds to the acre. That is not much! Why? because grass grows in over time if you encourage it.

If you question this logic, think of the reverse. The worst thing you can do for a pasture is to have too few animals on too big of a pasture. In other words they can pick and chose what they eat, and just like with children, if given a choice between candy and spinach, they take candy. Sheep are no different. Mob grazing works because it forces sheep to graze what they don't really want, just as you don't allow children a choice between candy and spinach at the dinner table.

Don't beat yourself up about not having paddocks set up yet, its a goal, we can see that and that is great. But until you get more sheep, or get paddocks set up, the best way to improve pasture is to mimic what mob grazing does. You have the tool for that, bushogging. The wonderful thing about grass ground is, all that chopped up grass acts as fertilizer and compost and improves your soil.

Here is a picture of a forest converted to field. The forest was cleared of tree in the winter of that year, then stumped in June, the rocks picked June through August, and then sown into grass in the first of August at the prescribed rate of 30 pounds to the acre. This picture was taken in October, and you can clearly see how patchy the ground is. Since then it has filled in very nicely. I can't take a picture of it just yet because we still have snow on the ground here, but its done well. Currently is is both pastured and bushogged.

One thing you could try and that is frost seeding which is tossing seed down onto ground so that freeze-thaw cycles draw the seed into the ground where it germinates and grows without having to till. I tried it several times with absolutely no success, but where you are located in KY it might work. That area is a big state and my only experience there was spending a few fall months in Paducha KY.

NOTE: Due to New England's tough winters, I had to seed this field down in August in order for the grass to be established enough root wise to survive winter-kill, or able to tolerate the cold.

What is the carrying capacity of your land in animal units per acre? In KY, I imagine it's quite high. It's possible you just don't have enough animals for your amount of pasture and you might consider allowing some of it to regrow to forest instead of fighting to maintain it.