Updated: Mar 2
Here at Petals we are committed to growing as many of our flowers locally, organically, and from seed. Seeds require three basic things to germinate properly: light, humidity, and heat. In this post I will detail how I control these three components of indoor seed starting and the equipment I use to guarantee blooms upon blooms every summer!
I started my seed starting adventure a few years ago by simply plopping some seeds in a pot of dirt on the windowsill...it did not go well. I think I got one sunflower seedling, which the rabbits ate within minutes of putting it outside. The next year I invested in a simple tabletop grow light and a 12 cell windowsill greenhouse, providing two of my three key components: light and humidity. I had better luck but my seeds took FOREVER to germinate and many of the seed cells within my greenhouse molded before anything grew. Then I finally broke down and bought a heat mat for my windowsill greenhouse, boy or boy did that do the trick! That year all 12 of the cells in my little windowsill greenhouse germinated producing little, bright green seedlings, much to my delight! The following year I went whole hog and bought two entire seed growing systems! This year I plan on adding a third system.
Light: I use two different systems for my growing. The largest is from Gardener's, an employee owned garden supply shop that is fantastic. I have bought everything from garden twine to seed starting towers and cedar growing beds from them. Their quality and customer service is impeccable! I have the base and one additionally stack-n-grow unit for a two story system exactly like the one pictured here. While surprisingly light weight, it is sturdy and the lights are fairly easy to adjust height-wise as your plants grow.
Humidity: To insure proper watering and humidity I use Gardener's seed starter kit, which is self-watering, dishwasher safe, and recycled! Unlike other systems I've tried (such as Burpee's version) that are flimsy and hard to move without damaging plants, the seed starting kits from Gardener's have stood up through three seasons of use already. They also sell replacement parts if one component does wear out. Their 24 cell kit is only $15.00 a piece if you buy three or more and, coincidentally, three fit perfectly on each level of their seed starting tower, so I have 6 for a total capacity of 144 seedlings started at a
Heat: The final component for successful seed starting is heat. Starting your seeds indoors, where the temperature is generally kept between 65 and 70 degrees, is a perfect start for growing seedlings but getting seeds to germinate requires a very specific type of heat, specifically under heat, which replicates the warming of the earth and soil that naturally occurs in the spring. We mimic ground warming indoors through heat mats. Gardener's sells three different sizes, none of which fit perfectly on their growing towers or under their growing kits so I use a combination of sizes and have had to do some trial and error in managing the heat mats. In the end, the fewer individual mats you can get away with the better because each have their own cord and when you combine the mat cords with the lighting cords it gets messy and complicated quickly (not to mention the fact that all of these electrical components will be in the proximity of water when you water your seedling so for the sake of safety it is necessary to limit your cords and keep them organized).
With some practice and the three components necessary for successful seed starting (light, heat, and humidity) you'll be on your way to growing bouquets full of blooms all summer long!