Ron Sweet posted a question on the Vermont Pasturelands Network that we think other folks probably have. It got a good answer from On Pasture author Dan Hudson
Hello!
I bought a couple of bags of red clover seed, and I was curious about the best time and way we should seed some of our weaker paddocks. My thought was to just pour it in a bucket and look for spots that could use some better growth and sprinkle seeds there by hand. Is it better to wait until after grazing season is over or do it now while the cows still have a few days out there (and can add more fertilizer, etc.)? Is by hand okay or is it better to use some type of manual seeder?
Ron
Hi Ron!
Great question! Seeding at the wrong time, in the wrong manner, or before you have corrected existing soil fertility problems often makes farmers regret spending money on seed.
If you spread the seed today and the red clover seeds germinated but did not reach the 3-5 trifoliate stage (which they probably would not), they will almost certainly be winter-killed – or severely injured.
If you wait until the soils and daytime temperatures are low enough that germination is unlikely, the risk of winter injury/mortality will be lower. Personally, I would be inclined to spread the seed after the ground is frozen or frost-seed it in the late winter. No-tilling it in the early spring is another option, although the grass growth provides a lot of competition during that time of year, even if it is a ‘weaker’ pasture.
The concept of no-tilling in early-August is a viable one too.   That allows you to bypass the extreme competition of early-spring growth and will increase the likelihood that the seedlings will have ample sunlight and reach the 3-5 trifoliate stage before winter. This depends on careful management of the last cut(tings) to allow the seedlings to receive ample sunlight. If you do no-till, be sure to keep the seeding depth shallow (1/4 inch or less).
Finally, it is always good to know why that field is ‘weaker.’  Soil fertility is a very common factor in situations where there is sub-optimal productivity, and it is a good idea to address/correct such issues before adding seed to the equation. Soil testing is the first step. (And here’s a link to the steps to collect soil for your test.)
When you do get to the seeding step, the best method depends on the nature of the problems. The cost of seed vs the value of your time usually leads to the conclusion that using an ATV-mounted spinner-spreader is a good approach for anything more than a very small area. Do some research before you purchase such a spreader, because there is a significant range in quality among models of spreaders.
For small areas, hand-held spreaders such as the Earthway 2750 can work (example, not endorsement). Be sure you understand the actual broadcast pattern and how to calibrate it/yourself. – the seeds are so small and going so fast that it is difficult to know exactly how much seed has gone where.
If you just have a few problem spots where the legumes have disappeared, reseeding those spots can work. Assuming that the seeds germinate, establish, and grow, you will probably have some patchiness no matter how you spread the seed. Reseeding only the poorest areas can easily result in a higher degree of patchiness. Such a non-uniform plant distribution is not necessarily a problem, but it can lead to non-uniform grazing, etc.
Whether you no-till, broadcast, or use livestock to tread in broadcast seed, the big three considerations are:
First, discover why the field is underperforming. Common causes are poor soil fertility, poor harvest management, compaction, excessive wetness, and poor water-holding capacity (such as in sandy soils).  Addressing the fundamental problems will increase your odds of success. Simply fixing the underlying problems is often more helpful than adding seed. Merely adding seed will not fix the underlying issues.
Next, work to achieve adequate seed-soil contact (not too deep).
Last, plan to manage the competition so seedlings can get fully established and compete with existing plants. This includes planting at an appropriate time, and may include clipping and/or strategic harvest/grazing activities.
Best of luck!
Dan
I have an experimental farm, using usually about six acres. The cows are moved according to grass growth patterns. After each grazing–up to five per year (see note below)–I walk through each pasture with my Earthway seeder and top-seed spots that are thin or in need of legumes. Mostly it is red clover with some trefoil and I’ll be trying Anik yellow alfalfa this year.
I omit the last top-seeding because of the reasons given in the article. Instead I frost seed in the spring, especially on paths and lanes with red clover and yellow (low-coumarin) sweet clover. The sweet clover punches through the packed soil.