When to Sow Outside: RECOMMENDED. In cold climates, sow flower mixes in the spring, 1 to 2 weeks before your average last frost date.
You can also sow half the seed mix 4 to 6 weeks before your average last frost date (hoping the last frost is earlier than usual), and then sow the second half a week or 2 after your average last frost date (just to be safe). The latest recommended spring sowing date is mid-June; after that time, conditions can be too warm and dry for germination and establishment.
In mild climates, sow seed during the cooler months. This will ensure an early display of annuals in the spring, and cool weather for germination and establishment of perennials.
When to Start Inside:Not recommended.
Special Sowing Instructions: Remove any weeds and amend the soil, if needed, prior to sowing. Rake the soil to loosen the surface. Shake packet before sowing to ensure even mixture of seeds. Using a rake, scratch in sand/seed mixture to a depth no greater than ¼".
Optional: Mixing seeds with sand can help spread seeds more evenly and the difference in color between the sand and soil can help remind you where to water.
Pro Tips: With a flower mix, it can be difficult to tell which of your seedlings are flowers and which are weeds. If you sow a pinch of seeds in a container of potting soil, you can then compare the flower seedlings with what sprouts in the garden.
You may also try first watering a prepared area in order to germinate the weeds; then eliminating the weeds before sowing flower seeds.
OPTIMAL GROWING CONDITIONS:
A soil test is the best way to know if you need to amend your soil. Usually, adding some compost or other organic material is helpful for establishing new plants.
Seeds must be kept moist until the majority of the seedlings emerge. This may mean watering once a day, twice a day for short periods of time, or every other day, depending on how fast your soil dries out and how much natural precipitation you get. You don't have to water deeply, just enough water to moisten the top quarter-inch of soil surface containing the seeds. Once the seedlings emerge, water less frequently and a little deeper; encourage deep roots by watering deeper each time you water.
Full sun for most mixes.
Not usually necessary.
The less square footage you cover, the more dense and smaller the plants may be, because seedlings that emerge very close to each other will compete for light and water, so some thinning may be necessary to encourage larger plants.
As the seeds begin to germinate, pull the seedlings you know are weeds. Continue to pull weeds frequently as your flower area continues to grow. If done on a regular basis, you will eventually have very few weeds to pull and lots of flowers to admire.