Planting Native Grasses and Wildflowers

We hope you enjoy our environmentally-sensitive native seed mixtures for Wetland and Wildlife Habitats and Reclamation areas where conventional turf practices are impractical. They’ll add beauty and seasonal interest along roadsides, industrial sites, parks, wetlands, and woodlots, and they are great alternatives to traditional lawn/meadow plantings.

With their ability to adapt to their natural surroundings and superior drought and heat tolerance, our mixtures offer an attractive alternative in the landscape while reducing erosion and providing food/shelter for wildlife.

Site Analysis

Meadow Sites

Meadows are defined by having moderately well-drained soil, silty loam, and clay-like but fertile soils with moderate organic content. Examples are: old farm fields, vacant lots, roadsides.

Wet Meadows & Riparian Sites

These are characterized by soils with high clay content or saturated sand. Examples are: roadsides, ditches, retention basins, pond areas, wetland edges.

Upland Sites

These are dry areas containing sandy, shale-like clays with very little topsoil. Upland sites need a little extra TLC — these sites will benefit from the addition of organic matter, lime, and fertilizer to improve soil fertility as per soil test results. Examples are: abandoned building sites, steep road cuts, naturally rocky hillsides and fields.

Woodland/Shaded Areas

You must loosen leaf litter to establish seed-to-soil contact while being careful not to disturb tree/shrub roots. The addition of topsoil/organic matter to improve soil fertility is important. Lime/fertilizer should be added per soil test results.

Wetland Sites

Moist, clay-like soils with high organic matter and impervious layers that prevent drainage. Examples are: wetland restoration sites, floodplains, ponds, retention basins.

Site Preparation

There is no doubt that re-establishing or creating new native plant ecosystems can be very difficult. We cannot stress enough that taking steps before seeding to limit competition from invasive, exotic, or undesirable vegetation during the establishment period is the single most important factor in the success or failure of your project.

Conduct a soil test prior to sowing to determine if the soil pH is within an optimum range of 5.5 to 6.5 for maximum nutrient uptake. If necessary, lime can be added to raise soil pH and agricultural sulphur can be added to lower soil pH.

Just prior to seeding, loosen the soil to 2.5cm (1”) in depth. Create microsites within the planting area by sculpting in minor ridges and hollows that can trap moisture. This will help improve germination of the native seed, especially in those areas that tend to be very dry projects.A few months to one year before scheduled planting, begin the process of eradicating existing vegetation by making several, repeated treatments with a low persistence glyphosate herbicide.

Where practical, a close mowing two weeks prior to spraying is beneficial as it will stimulate plant growth and help to ensure that the herbicide is effective. A light cultivation to 2.5cm (1”) deep between spray applications will stimulate dormant weed seed in the soil and encourage sprouting. Heavy cultivation is not recommended at any time in the process.

Sowing the Seed

Evenly drill or broadcast the seed by hand, or with applicators, across the prepared area. Two half-rate passes made at right angles to each other will produce a more even job than one full rate pass. When hydroseeding these mixes, we recommended that the application rate be increased by 50 to 75%. Where practical, roll the soil after seeding or otherwise press the seed into the soil to ensure there is good contact at the seed/soil interface.

Do not attempt to cover the seed with soil as rain, frost, and snow will work the seed into the soil. If you do wish to use protective mulch, a thin layer of clean straw (free of weed seed) can be applied over the seeded area.

Sowing Rates

Mixes are designed to be planted at 25 kg/ha (23 lbs/acre) or 250g/90 sq. metre (½ lb/1000 sq. ft.). Seed annual ryegrass or oats as a nurse crop and for erosion and weed control at 22 kg/ha (20 lbs/acre).

Nurse Crops for Native Plantings

We highly recommend mixing the seed with a nurse crop. In the short term, the seed of the nurse crop will help to bulk-up the mix making application easier. In the long term, the nurse crop germinates quickly to help cover and protect the native seed mixes during their germination and establishment periods.

Annual rye or oats will make a suitable nurse crop as it helps to suppress weeds before disappearing from the planting. Canada Wild Rye, a cool season early succession native grass, can also be used as it establishes quickly and helps suppress weeds before gradually disappearing from the planting.

It is not advisable to use winter wheat, ryegrass, or fall rye because these are aggressive species that often persist within the planting. There is some thought that they also release toxins that interfere with the growth of other plants.

When applying nurse crops, we recommend that you do not apply them at a rate higher than suggested. When nurse crops are applied at a higher rate, they can outcompete the target plants and prevent them from becoming established — this is the exact opposite of what is intended.

Time of Planting

The seed from most native species will have improved germination rates if the seed goes through a cold stratification (a process that helps break seed dormancy). For this reason, we recommend planting in the fall between early October to late November.

An early spring sowing is also suitable, however, germination rates can be initially slower or slower overall. It is important to note that regardless of the time of sowing, if moisture is lacking during the germination period, seed can remain dormant and not germinate until conditions are suitable.

Cold Stratification of Native Seed

When seed is sown in the fall, cold stratification will occur naturally though the winter.

Seed can be cold stratified without planting outdoors using two methods.

  1. In the cold/dry method, which is preferred by most native grasses, simply place the seed in a protective container and set it in a refrigerator or unheated building for 2 months during the winter.
  2. In cold/moist stratification, which is preferred by most wetland forbs (a forb is a flowering plant) sedges and rushes, mix the seed with a moistened soil-less medium in a container, seal the container shut and place it in a refrigerator for 2 months.

Seed can also be planted in small pots or trays using a moistened soilless medium. Cover the containers to keep the medium from drying, then place them in the refrigerator or in an unheated building or cold frame for two months during the winter.

Establishment and General Maintenance of Native Plantings

The establishment of habitats from native plant seed mixes does not happen overnight. In many cases, it will take 2 to 4 years for the full extent of the planting to express itself. Why is this the case?

First, many native plants are warm soil plants and their seed will not sprout, nor will their yearly growth start, until the soil warms up — which can be as late as mid-June.

Secondly, for their first year of growth, prairie plants are like icebergs. While you will see a small amount of top growth, most of the growth occurs in the soil where these plants put down an extensive root system — in some cases up to 3m (9’) deep!

It is this extensive root system that makes prairie plants so drought resistant. It is also this deep, extensive root system that allows them to mine the subsoil for nutrients and cycle them upwards, and conversely introduce large amounts of organic matter downwards – two processes that have tremendous long-term benefits for the health and fertility of the upper soil horizon.

The last point to keep in mind is that some species are early successional and establish during the first 2 to 4 years from planting, while some species are late successional and do not establish until 3 or more years after planting.

Note: When undesirable vegetation reaches 30 – 45 cm (12 – 18”) height, mow to no less than 15 cm to prevent weed seeds from developing seeds. Generally, native plants will grow more root systems than tops the first year. Do not mow with a lawn mower, as mowing too close encourages weedy growth.

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