As mentioned in my previous marigold blogs, we are embarking on an experiment to answer the question: what is the best or easiest way to grow French marigolds? The group, consisting of Master Gardner (MG) trainees and MG observers of the propagation lab, will be divided into three groups: starting seeds indoors, using milk jugs outdoors, and sowing seeds directly into the garden. The last procedure is the focus of this blog. Our end goal is to have marigolds to offer for sale at the RAMGA plant sale on May 11th. I will also be planting using each technique and hope that we can guide each other through this experiment.
The Seed
I harvested seeds from French marigolds (Tagetes patula) during the summer and fall of 2023. They were stored in a dry, dark cabinet at room temperature and will be distributed to the group during the propagation lab in February.
The Garden
I call these marigolds “miracle” because that’s what it is going to take to produce a decent sized plant outside by May 11th. Our biggest challenge will be dealing with the weather. Despite our recent categorization of USDA plant hardiness zone as “7a”, the earliest last frost date is April 15th. We have calculated a propagation time requirement of at least 8 weeks to allow for germination, growth, and potting up. So, mother nature will need some help. Here is a brief article that suggests using clear plastic or cloches to warm the soil: https://www.rhs.org.uk/propagation/pre-warm-soil.
I have also seen cardboard suggested to warm the soil, and you could consider using the milk jugs as a cloche, but you will need to secure them into the soil.
Otherwise, we will follow the recommendations outlined in the MG article “Outdoor Seed Sowing” https://www.ramga.org/_files/ugd/c80da7_62bf5e8b5cab4b0faae71876fc46d969.pdf
and will plant to a depth of about ¼”, thinning to 8-10”.
Start Date
Begin preparing the soil ASAP and plant whenever you can get the soil warm enough for germination, usually about 65 degrees F. You might want to try successive plantings a week or two apart.
Good luck! Please post a comment to this blog if you have any questions.
January 27, 2024
Yesterday I prepped the soil in a spot in my garden with compost and covered a small portion with thick, clear plastic. I also secured a milk jug with the bottom cut out to an adjacent area using some spikes I found in the barn. We'll see which one works the best. Fingers crossed.
March 16, 2024
I decided to go ahead and try sowing the seeds this past Tuesday (the 12th) since the ones in the other milk jug had sprouted. Today, I noticed several small sprouts that look like marigolds peeking through the soil. I also noticed what looks like marigold sprouts where I had a few plants last year, though I admit it's hard to tell since several other things that I did not sow seem to be coming up (like chickweed).
March 28, 2024
Took a quick pic of the marigolds sprouting (at left).
April 7, 2024
NO seedling survived our recent cold snap! Some seeds may sprout later but based on the time needed to grow, I don't think I'll be contributing any "miracle marigolds" to the plant sale.
Anybody out there with success using this method?