Everyone's Quick Guide To Seed Starting

17 comments by Halley -Author at MIGardener

Seed Sourcing

Sourcing seeds is a very important aspect of growing from seed. Make sure you are purchasing seeds from a reputable source! MIgardener is a great resource for heirloom seeds!


Natural Growing Days
Knowing the 'natural growing' days in your zone helps you build a plan on when to start plants and how to schedule succession planting. For more info, see the blog!

What do I mean by 'natural growing' days? This term refers to the date span in between two important dates to all growers. Your last estimated frost (LEF) date and your first estimated frost (FEF) date at the end of your season. For instance here in 6A, my LEF date is May 11th 2022 and my FEF date is October 7, 2022. Between these two dates, I have approximately 154 natural growing days.

For those of you who watch Roots Shoots & Coffee on Tuesday Mornings at 9:30 a.m. EST., know that I hit this idea hard. Knowing this information gives you a starting point to figure out any scheduling detail. 

Sift Or Not To Sift?
Sift your seed starting mix! I'll be honest, it took me a few season to jump on this ship. Now that I am on, I refuse to get off! The difference that sifted soil has made on my plant starts is so easy to see. My initial hold back was based on the idea that if I were to baby my plant starts too much I would be doing myself a disservice and ending up with weaker over all plants. This theory has it's place. What I wasn't taking into account was the amount of growing real estate that my plants had to get started in plug trays. Obviously when we direct sow, there may be many obstacles for seedling's roots to work around but think, they have a whole bed of space to make those moves. When sowing seeds in plug trays or small containers, seedling's root systems only have so much room. If you were to have, say, a large piece of coco coir in your container, seedling roots cannot break through that. 

Sifting soil gives you a homogenous growing medium for your starts to grow in. Just remember this doesn't mean we want to baby our plants off the bat, this is just one battle that won't be beneficial to us in the end. 

Important Stressor To Add To Our Starts

Here is where that theory comes into play. When we are growing in an unnatural environment, like our homes or an enclosed greenhouse, we need to simulate factors plants would receive if they were direct sown. Wind is not something that immediately comes to mind, at least it didn't my first year starting seeds in my home.

Adding a fan to stimulate air movement in the room (not directly on your plant starts) is a necessary stressor to apply to our new starts.  This will help to strengthen their stems, giving you the strongest plants to get started with. 


When To Fertilize

Can you and should you add fertilizer to your seed starting mix? You do not want to add water soluble fertilizer to your seed starting mix. Seeds have all they need inside their shells to grow into seedlings. Not until your seedlings produce their first set of true leaves, do you need to feed them. If you were to use a water soluble fertilizer the nutrients would be washed away with each watering you do.

You can mix a slow-release, non-water soluble, fertilizer in with your seed starting mix. The benefit of this is to eliminate the step of fertilizing after your seedlings have emerged. I had questioned in the past if watering would eventually start taking out nutrients even though its not immediately water soluble. The answer is that you may loose a bit but the majority of the nutrients are ready when needed. For those of you who have started seeds before, you know that not every seed pops out of the soil at the exact same time. This means that each seedling will earn it's true leaves at different times as well. Having the fertilizer mixed in makes it so that it is ready to rock once each plant reaches that stage! 


Let There Be Light
Grow lights will make or break the strength of your plant starts. On the other hand, grow lights don't need to break the bank! When looking at grow lights the most important factors to look at are the Kelvin and the Lumen capacities.

Kalvin describes the color temperature of a light source. Typically for starting from seeds requires lights that are at minimum 5000 Kalvin but I like mine to be closer to 6000 Kalvin. 

Lumen refers to the brightness of the light given off. For starting seeds we require a Lumen capacity of 3000 to have enough light for proper and strong growth. 

Here is an option for linkable grow lights that I love! Here is a 4 light system. It works out that buying more than one set of 4 works out to be less expensive than the larger packs. I have had these lights for three years now and have seed great success!


Remember that what works for me won't always be the perfect plan for you. My goal is give you the tools you need to find context clues that help to determine what will work in your environment! Use this information as a guideline and take your growing conditions (even indoors) into consideration! 

-- Halley @MIgardener




  • Linda Jean

    Hey Luke and gang up north:
    My nature is adventure. I will experiment as I started tomatoes in little peat squares with peat moss only. When they sprouted, I sprinkled some nice, loose soil on them and will plant in the morning because we have a hot spell coming. Love your vids Luke. Have no plans to do the “indoor with lights” thing. Seems like daycare for seedlings..ha ha.

  • Evangelina Covert

    Thank you very much for the grow light description, it is very informative. Thank you to you and your staff.

  • Richard

    I confused by the term: “non-water soluble, fertilizer” How does it break down?

  • Ms. Parker

    I very new to gardening but I already love it. I prefer container gardening. I have never used grow lights or mats. Poor success with my first fall seed starting. Ready to start again. In zone 9A. When do I use grow mats and lights?

  • Cindy Watson

    When will you be getting more sweet corn seeds in stock? I want to put some in my fall garden.

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