How to Plant Flowers in the Fall & Winter
In this post, we are providing much more information about the tips we offer in our Fall & Winter Planted Flower Guide. Nell Frazer Lindquist, our Inventory Manager, offers a deeper explanation of how cold stratification works here. Nell served as the first-ever Nursery and Greenhouse Coordinator at the Idaho Botanical Garden, where she grew thousands of plants annually for garden use and plant sales
To cold-stratify your seeds indoors you can use simple items you may have at home!
The bag method:
For this, you will need a sandwich bag (used is fine, so long as it's clean and dry to begin with), about 1/4 cup of sand (playground sand from the hardware store is great), and a permanent marker. For transplanting in the coming months, you will want to have small pots or seed trays and seed starting mix.
If you're stratifying small seeds, like Goldenrod, you can use one packet for one bag. If you are using larger seeds, such as the Antelope Bitterbrush, you may want to use two bags.
- Use your permanent marker to label the bag with the seed name and date of starting.
- Fill your sandwich bag with sand.
- Sprinkle the seeds in the bag.
- Close and shake the bag to mix them thoroughly.
- Open the bag and moisten the sand enough to be sure it's all wet, but avoid adding too much water. Standing water may encourage mold growth.
- Store them in the refrigerator for the amount of time specified on the packet's planting directions. You can check them 1-2 times per month to be sure there is no mold growth, and see when the seeds have started to sprout.
- When they do begin to sprout, you can transplant them into prepared seed trays or pots filled with seed-starting soil.
- You can gently pluck seeds that have started sprouting out a few at a time, leaving un-sprouted seeds in the bag to continue doing their thing.
- Prepare your small pots or soil-filled seed trays by making a small hole in the soil for each new plant start.
- Using a small teaspoon, butter knife, or a skinny fork, lift out each started seed, avoiding the new growth as much as possible, and place it carefully in the hole. Be sure your pots and trays are labeled with the plant name, start date, and transplant date!
- If you are starting small seeds this way, you can broadcast the sand and seeds over flats or pots filled with starting mix.
Paper Towel Method:
Nell's preferred method is to use paper towels or coffee filters. For the home gardener, this works well for medium to large seeds. For this, you will need a paper towel, a ballpoint pen, and a 1-gallon freezer zip-sealing bag. For transplanting in the coming months, you will want to have small pots or seed trays and a seed starting mix.
- Write the seed name and date with the pen on the dry paper towel.
- Evenly distribute the seeds over half of the paper towel. Use multiple paper towels if needed.
- Fold the paper towel in half and moisten it. Some may find it easier to moisten the paper towel before spreading the seeds over it. Try it and see what works!
- Place the paper towel in the bag, seal, and store in the refrigerator until you see sprouts.
- Only moisten the paper towel enough to be sure it's saturated, but not excessively wet. Standing water in the bag may encourage mold.
- Squeeze all of the air from the bag when the above steps are completed. Nell likes to put the bag inside another container in my fridge - a jar or something like that - to make sure that nothing in my fridge that emits ethylene affects the seeds.
- Check the bag regularly - 1-2 times per month to see when your seeds are healthy and sprouting, and be sure there is no mold.
- Once the seeds have been in the refrigerator for the allotted time on the seed packet, transplant each seed or sprout into prepared small pots, or seed trays filled with a seed starting mix.
- Prepare your small pots or soil-filled seed trays by making a small hole in the soil for each new plant start. Be sure your pots and trays are labeled with the plant name, start date, and transplant date!
- To avoid disturbing the new plant growth as much as possible, you can carefully tear or cut the paper towel into small pieces. You can also use tweezers to great effect here! Be sure to transfer them into the seed starting mix root-side down! This will vary in appearance based on the seed.
- When the seedlings are 2-6 inches high with at least 2 sets of leaves (variety dependent) they are ready to transplant into the garden.
The Outdoor Tray Method:
You can sow your seeds into prepared pots or flats outside, and then transplant them in the spring after they germinate. This works well for small seeds that aren't as easy to directly place on a paper towel.
- Prepare your small pots or soil-filled seed trays with seed starter mix. Be sure to label it with the name of the plant and the date you sowed your seed. You want to use something permanent, like a Sharpie, garden marker, or pencil. Plastic plant tags, recycled mini blinds, or metal tags are the most durable.
- Broadcast your seeds directly over the prepared flat or pots. Some seeds need the light to germinate. If the seed has a suggested planting depth, add that amount of soil on top of your broadcast seeds and gently pat it down.
- Protect your freshly sowed seeds from squirrels, birds, soccer balls, romping dogs, etc!
- Make sure to keep the soil in your seed trays moist, but not soggy. If they get a nice cover of snow, they can hang out until the weather warms up.