Wildflower Seed: Planting In Fall

Fall is the perfect time to plant wildflowers. You'll follow Mother Nature's cycle - flowers naturally drop their seeds in the fall, and they overwinter, then germinate and bloom in spring. Fall planting is an especially good time to plant in areas where you want to conserve water. Follow our step-by-step guide to planting in fall, below!

Seeds are a miracle of nature, holding the spark of life inside themselves that can stay viable for many years, even decades or centuries if storage conditions are optimum. Seeds are also a very cost-effective way to plant your property with a wide variety of wildflower species, especially when rehabilitating or restoring larger yards and fields.

• Timing Your Planting: When To Sow Seeds
• The Keys To Seeding Success
• 6 Steps To Understanding Your Planting Site
• Remove Existing Growth & Prepare The Soil 
• Scatter Seeds Evenly
• Press Seeds Into The Soil
• Watering Your Wildflowers
• Meadow Maintenance & Weed Control
• Wildflower Seeds For Your Fall Planting

You can mimic mother nature and sow either in the fall or winter, depending on your region.

In climates with cold or freezing winters, wait until November or early December to sow the seeds. You want to have several hard frosts and freezing nights, so that the soil cools sufficiently to well below 55 degrees, so that your seeds don't sprout prematurely. Or, wait until a big snow is predicted, and scatter the seed before the snow flies.

In warm winter climates that do not get a winter freeze, wait until the late fall/winter rains to sow the seeds. This will provide ideal germinating conditions. Winter sowing is especially helpful in desert climates, where the hot weather arrives very quickly in spring and creates hot, dry conditions that can kill tender seedlings.

It's essential that you know at least a few basic details of your plant site.

1. Understand the condition and existing vegetation on the planting site. This is very important to the long-term success of your seeding project. If you are seeding into what used to be a lawn or recently cultivated crop field, the time needed to prepare the site for planting is much less than seeding an old overgrown farm field choked with weeds and shrubs or other invasive species. If your area to be seeded has a lot of desirable species already on site, you may just need to prepare small pockets scattered around the site to seed while leaving the established plants undisturbed.
2. Measure and calculate the square footage of the area to be seeded. This is essential for determining how much seed will be needed. See coverage rates on each product page. It's important not to use more seed that you need - this will cause overcrowding and can prevent healthy growth.
3. Determine your soil type. It is especially important to know if you have clay or sandy soil. Other soil types are generally suitable for wide range of species. But clay and sandy soils will necessitate choosing wildflower species that prefer them.
4. Know your directions. Where's north? This will help you identify shady areas around trees and buildings. South-facing spaces will receive the most sunlight throughout the day.
5. Find out if there is a slope to your property and know the direction of the slope. A north-facing slope will have colder soils that a south-facing slope and may require a different seed mix in very cold climates.
6. Identify trees and buildings that cast shade onto the planting site. Wildflowers generally require at least 6 hours of sun.

If the area to be seeded is a lawn or weedy patch, then it's important to get rid of the lawn grasses or weeds. It's important to remove these existing plants to give your wildflower seeds the space and access to nutrients that they need to thrive. There are several methods you can use to clear your site of existing growth:

• Smothering: This can be done one of two ways. If you want to improve soil quality or bring life back to compacted or damaged soils, covering the area with corrugated cardboard and newspaper. Then bury with a 6-to-8-inch layer of fine-textured wood chips or compost. Water every couple of weeks in hot dry weather. And in 4 to 8 months, all the weeds/lawn grass will be dead and the area ready to rototill. Alternately, you can cover the area with heavyweight tarps to create dark, moist conditions that will kill and rot the weeds/lawn grass. Note that this will not greatly improve the soil's tilth and nutrient content.
• Solarizing: If you have 6 or more months until you want to plant, this is a great option. Cover the lawn grass or weeds with clear plastic and bury the edges for 6 to 8 weeks during the heat of late spring/summer, and the heat of the sun will cook the weeds and grass. Afterward, the area should be rototilled and raked to remove all the dead plant debris.
• Careful use of herbicides: if you have 3 or more months until you want to plant, the judicious use of systemic herbicides is an option. Use protective gloves and clothing. And remember, a healthy living soil can break down herbicides when used sparingly. Rototill the area after the lawn grass/weeds are completely dead.

Create a Nice Seed Bed

Once the existing plants have been killed off, rototilling should be done to prepare the soil as a seedbed. Repeat several times - this will encourage weed seed germination, and eliminate dormant weed seeds that sprout after being brought to the surface.

When you're ready to seed, give the area the last rototilling about 2 to 3 inches deep, and rake with a stiff bow rake to break up the dirt clods and create a smooth, even-textured soil surface.

Unless you’re seeding a very large area, it's best to scatter your seeds by hand for even distribution.

Mix seeds into dry sand (we recommend bagged playground sand to avoid contamination), used as a filler to more evenly distribute the seeds. a cup of seed to 8 cups of sand is a good ratio. 

In larger areas, divide the planting area and the seed mix into smaller parts to more evenly spread the seeds. For example, if you're seeding 1,000 sq ft, divide the area into four even parts and divide the seed needed to cover that area into the same number of portions.

Mix in a couple of tablespoons of Plant Success Granular Mycorrhizal Spores into the sand & seed mix to improve seed germination and seedling vigor.

Once the seeds have been sown, you need to press the seeds into the soil to ensure good germination. This is better than trying to cover the seeds with soil.

Use a sod roller, a small 2 ft x 2 ft piece of plywood or cardboard that you can stand on to firm the soil around the seeds.

Wildflower seeds need to stay consistently moist from germination until they are about 4-6 inches tall, which is about 4-6 weeks. Typically, a major advantage of fall and winter plantings is that they do not need supplemental watering in most locations.

It can be helpful to have some sprinklers available to irrigate the seedlings beginning in mid-spring if conditions are dry. If dry conditions continue into the summer, turn on the sprinklers to put down about 1/2 inch of water once every one to two weeks. Sandy soils may need a bit more frequent watering when it gets hot and dry more often.

Pulling or snipping weeds will help to encourage healthy growth in your wildflowers. This can be done by hand weeding in small areas, or mowing in larger areas where hand weeding isn't practical.

Be sure you can identify seedlings of the seeds you sowed so that you don't weed them out by accident. You can use a plant identification app, or wait until the weeds bloom to cut them if you are not sure if it is a weed or a wildflower. 

• Hand Weeding. It's better to cut the weeds off just below the soil line with a weed fork or a Hori Hori knife (or similar implement) instead of pulling the weeds. Pulling weeds disturbs the soil and actually creates a new seedbed for existing seeds in the soil, or seeds that blow into the area, to germinate.
• Mowing. Mowing large seeded areas during the growing season is a great option for helping your seedlings to establish themselves by limiting competition from weeds. You can use a lawn mower or string trimmer. Set the mower deck to a height of 4 to 5 inches and mow when the weeds reach about 8 inches tall. Repeat as needed through the first growing season. If weeds persist during the second year, additional mowing will be helpful.

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