You can frost seed switch grass in November or March, you can plant it into tilled or untilled soil in May or June, it will not germinate until the soil has reached the sixties. If you plant it thick enough you will get a satisfactory emergence, no matter when you plant it.
What is your goal? What is the ideal planting date for maximum germination and emergence and why?
We intend to plant at least 30 acres of Cave In Rock switch grass this year. I called Jim Truax, (inventer and builder of the well known Truax warm season no-till planter) last winter and asked for his advice as well as several others in the business. Jim gave me the most sound advice and I intend to follow it.
Jim advices differant seeding rates of switch grass for differant applications. You can seed switch grass at 10 lbs per acre for a crop, (cattle will eat it if harvested young). You can seed it up to 5 lbs per acre for cover and nesting for pheasants. That's the maximum rate but Jim recommends something less like 3-4 lbs per acre. This stuff is aggresive and may get a bit thick for pheasants. It does grow in bunch's, (clumps), which is ideal for game birds and allows them to scoot about within it. Yet it can get too thick under ideal growing conditions.
I told Jim that I intend to include a perenial blend of legumes and forage soghumn with the Cave in Rock. He asked me how much of each I intended to plant. I told him that I was advised to plant the Cave in Rock at 5 lbs per acre and due to the early sensitivity of switch grass, (it doesn't like competition) I intended to add only 4-5 lbs of a perennial blend and 5 lbs of forage sorghumn.
Jim agreed about the switch grass not liking competition and advised me to lower the perennial blend to 2 lbs per acre or none at all. JIm was a bit skeptical about forage sorghumn for it is very aggresive and will grow up to 10 feet tall, thus putting the hurt on the switch grass. I told Jim my reasoning for the forage sorghumn. It may take three years for the Cave in Rock to reach its normal 7 feet height, while the sorghumn will grow for only one year , reach up to 10 feet and give me the cover the first year. JIm saw my goal and advised to keep the seeding rate for sorghumn under 4 lbs per acre or no sorghumn at all.
Jim then said, "Ed you are planting Cave In Rock switch grass for cover for deer and this changes the picture quite a bit. Switch grass grows in clumps and grows aggresivly once it gets established. Cave In Rock is the most aggresive switch grass available and needs special consideration". Jim then discribed these special considerations. "You want these clumps to grow large in size and spread apart to allow deer to move easily within your field. If the seeding is too thick, deer and also you Ed will have a very difficult time moving about in these fields". They will bed in the field but near the edges and not move about very much and that's not what you want, since you told me that you intend to plant a long winding 48 foot wide strip of a variety of forage within this switch grass field.. I advise absolutely no more than 2 1/2 lbs of Cave In Rock per acre in poorer soils and at low as 1 lb per acre for the better soils".
JIm also advised that I get rid of the weed competition before I plant and that no-till is advised, along with the end of June to the first of July for the seeding date. JIm then told me why to plant at the end of June. As mentioned switch grass germinates at soil temperture in the sixties. If you plant sooner it wont emerge while the weeds and or seeds planted along with it, (my situation) will get a head start. So give that switch grass, which is slow to start an even chance to compete. You will also achieve a better gemination rate.
Jim Truax I believe is a good source for info when planting Cave In Rock switch grass.
I have one 9 1/2 acre field that was sprayed last September and over 20 other acres that were sprayed mid May this year. I will spray again all fields the day before I intend to plant in late June or the July fourth weekend using a Truax no-till drill rented from the Gladwin Soil District. This is all no-till.
My seeding rate will be as follows, Cave In Rock at 1 1/2 lb per acre, our Michigan's Ultimate perennial blend minus the nurse seed of brassicas at 2 lb per acre and Forage Sorghumn Sudan BMR at 3-4 lbs per acre or none at all. Based on my experience of previous plantings of switch grass and forage sorghumn I expect some action this year.