Zinnias are one of the most beautiful flowering, annual plants. They are no-fuss, high flower producing plants that anyone can grow. They come in varying heights, bloom colors, and bloom types, which means there’s a Zinnia for every size garden and gardener. Zinnias are drought tolerant and love full sun, but will still produce blooms in part sun/shade. Zinnias can be started from seed 4-6 weeks before your last frost date. If you are unsure of your last frost date, you can find it on this site.
Disclosure: This post is sponsored by Park Seed. Thank you to Park Seed for supplying the Zinnia Seeds for this post.
To grow Zinnias from seed, you will need proper light, water, soil, and air flow.
Seed starting pots
Seed starting soil
Grow light or Window light
Before starting your Zinnia seeds, you will want to have “seed starting pots,” which can look like many things. I am using seed starting trays from Amazon, and they’re perfect for starting seed, plus you can reuse them year after year. If you plan to reuse pot, be sure to sterilize them prior to use. Seedlings are prone to damping off, so using sterile pots can aid in keeping them healthy and happy.
Fill your seed starting pots/trays with seed starting mix. This type of mix is important for healthy, happy seedlings. Seed starting soil is actually soilless, fluffy and perfect for seedlings to root and get established.
PRO TIP: You can pre moisten your soil prior to filling your trays.
It’s time to plant your seeds. Take two Zinnia seeds and plant them 1/4th of an inch into the soil of each cell then cover. Planting two seeds is a great idea just in case one doesn’t germinate. If both seeds germinate, you can divide them when they have their first set of “true leaves” or you can snip the weaker seedling down to soil level.
FUN FACT: Zinnias were the first flowers to bloom in space! Check out this article to read more!
Bottom watering is best when your seeds have not sprouted or are very young. Watering overhead can displace seeds and break new seedlings.
Keep your seedlings in a warm room that stays consistently 50 degrees Fahrenheit or higher temps with a grow light above your seed trays or in a bright sunny window.
Pro Tip: If you are using sunlight to grow your seedlings, make sure to rotate the seed trays to help with leaning and leggy seedlings.
As your seedlings grow, you can begin incorporating a diluted amount of fertilizer weekly. Once you’ve reached your frost-free date, it’s time to wean your seedlings for outdoor life.
When your frost free date has passed pick a sunny spot in the garden and plant your Zinnia seedlings. Keep them well watered and they will reward you with beautiful cut and come again blooms all season long.
Zinnias are one of the easiest plants to start from seed. The seeds readily sprout and eagerly grow into plants that bloom all summer long, providing gorgeous blooms for you to enjoy in the garden or in bouquets indoors.