How To Plant Prairiegrasses
Preparing to Plant
Eliminate any undesirable plant by either chemical or tillage treatment. Removing aggressive cool-season sod forming grasses is a must before planting a wildflower or prairiegrass site. Several commercial herbicides are available with Round-Up being the most popular and least toxic. Planning a year ahead allows the best chance for success of eliminating sod forming grasses as it may take more than one application for complete control. Fall application of herbicide is normally the best followed by another application in the early spring if necessary. Once again, it is very important to eliminate these grasses because they can come back to invade your planting in future years. Dead thatch must be removed by burning, raking or tillage if not using a no-till grass drill. Refer to labels for required notes and directions.
Repeated tillage is the other option available to control undesired plant growth. In cases of sod forming grasses, this will take a season of repeated tilling before planting. The first flushes of weed growth in the spring can be avoided by one or two light tillings to destroy growth prior to planting.
The use of a starter fertilizer with slow release nitrogen is recommended. Even though native plants are efficient users of water and nutrients, having those nutrients available stimulates root and vegetative growth for healthy seedlings. On disturbed soils, such as areas around a new building site, water and sewer lines, fill dirt, etc., it is very essential to add soil amendments to germinate seed and maintain the vigor of the small seedlings. In areas exhibiting difficulty in establishment a soil test may reveal any existing problems.
Many of the native warm-season grass seeds are fluffy in nature and are not flowable enough to be seeded through most conventional drills. Large areas (over 1/2 acre) are easiest to plant with a native grass drill. These drills have a special feeding mechanism and agitator to evenly distribute seeds at a uniform depth in the soil. Easy flow type fertilizer spreaders also can be used to distribute the seed over the area. Smaller areas can be broadcast-seeded by hand. Mixing seed with sand and vermiculite or sawdust can help distribute the seed more evenly to cover the entire area. This especially applies to wildflower mixtures with different size seed.
Plant into a clean, firm seedbed, free of clumps for optimum seed-to-soil contact. Loose soil dries out quickly at the surface compared to firm soil. Also, seed may be planted too deep in loose soil, as grass and wildflower seed should be planted from 1/4 to 1/2 inch deep, with wildflowers planted at the more shallow depth. One major cause of failure is planting too deep.
Most drills have packer wheels or a cultipacker roller to firm the soil after seed has been placed. After broadcasting seed, it must still be planted by raking, harrowing or pulling a straight set disc back and forth over the area to place the seed at the desirable depth (1/4 to 1/2 inch). Then, it must be rolled or cultipacked to firm the seed with the soil. A good measure of a firm seedbed is to sink no more than 1/2 inch when walking on it. Straw mulch, or erosion control blankets may be used if not applied to thickly, as warm season grasses and wildflowers need sunlight at emergence and may smother if mulch is too dense to allow for light penetration.
Leftover seed should be stored in a cool, dry place as heat and humidity can cause loss of germination. Properly stored seed should remain viable for planting the following year with minimal loss of germination.