• Briana Bosch

seed starting 101

One of the biggest questions I get is how to start seeds! We start almost 100% of our plants here in our annual field as seeds, because they have a lower environmental impact than plugs (small seedlings ready to plant) when it comes to shipping, and they're also a lot cheaper--a big consideration when you're planting 10,000 of them!

Even if you aren't planting 10,000 seedlings, starting with seeds allows you to select more unique and exciting flowers than buying plugs or plants from your local nursery. The possibilities are endless...IF you know what you're doing!

Know what you're working with!

Every seed has different starting instructions--some need light for germination, some need dark. Some need to be planted deeply, others only sown on the surface. Temperature is another big factor. So step one is to do your research on what the seeds you're starting need, which will guide the process of starting them. Here are a few things to keep in mind:

When to start: One of the biggest mistakes people make is starting their seeds much too early. Pay attention to the seed packet--I like to work my way back from my planting date (our average last frost in Colorado is May 15-ish, but I don't plant until a week or two after that). So if I was planning to plant on May 22, I would work backward 6-8 weeks from there to start seeds that recommend starting 6-8 weeks before last frost. Of course, you can start earlier (and many people do), but seedlings that sit in their trays for too long will become stressed at the root and will be more draught and pest-sensitive once they get planted. Studies have also shown that if plants are too large when they get transplanted, they have reduced yield. So don't start your tomatoes in January just so you can transplant bigger plants--it's best to transplant them before they've flowered to ensure success.

Light/Dark: Seeds that need light to germinate are generally sown on the surface of the soil. Care must be taken when watering to ensure you don't wash these small seeds away; I mist with a spray bottle twice daily until germination occurs.

Dome them: By putting a dome (I use clear for seeds that night light for germination and black for seeds that need darkness--just be sure to remove the dark dome after germination so your seedlings don't get light deprived) on top of the tray, it helps the seeds stay moist, a key to germination.

Heat mat: Most seedlings like soil that's a bit warmer for germination. It's not necessary, but a heat mat will help your seeds germinate at the same time, rather than spottily.

Soil: I get a LOT of questions about this! If you're starting on a small scale in seed trays, I would recommend Jiffy's Organic seed starting mix. However, on the farm we soil block, so we use a mix of 80% Vermont Compost Company Fort Vee mix and 20% Jiffy's Organic seed starting mix for our 3/4" soil blocks and 100% Fort Vee mix for our 2" soil blocks. We will be posting a blog about our soil blocking methods, so check back!

Check in: Don't forget to check on your seeds regularly! You don't want them drying out, and if they are germinating in the dark you want to be sure to move them to the light once they start germinating so they don't get leggy. Check out our troubleshooting guide for seed starts for more info, coming soon!

If you want to learn more about seed starting, be sure to check out our Planning & Planting a Cut Flower Garden class at Blossom & Branch Farm, where you'll learn all the basics and try soil blocking hands on! Happy seed starting!


2440 Iris Street

Lakewood, CO 80215

(720) 319-0243


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