Starting seeds indoors is a fun activity that helps you make the most of a short gardening season, but some seeds are harder to germinate than others. In this video, I share tips and tricks for seed germination success.
Outdoors, Mother Nature does a great job of breaking through the seed coat of tough seeds. Indoors, we can help that process along a few different ways.
The Warm Soak
To soften their hard outer layer, some seeds benefit from a soak in warm water before planting. Simply place the seeds in a cup of warm (but not boiling) water and set them aside for 24 hours before planting as usual.
Okra, peas, beans and nasturtiums are just a few examples of seeds that are suited to the warm soak method.
Scarification is the processing of breaking through extremely hard seed coats by scarring or scratching the seed surface. This allows air and water to permeate the seed so germination can begin. Only a little bit of the seed coat needs to be removed to be effective.
Take a seed and rub it on sandpaper just until you see the color change. Alternatively, you can use a file.
Some seeds, like beans, have a white dot where the shoot will emerge from. To avoid damaging the eye of the seed, scratch the opposite side.
Stratification simulates nature’s ebbs and flows of winter and early spring, as many perennial seeds and tree seeds require that temperature variability to cue them to sprout.
Place seeds in a plastic bag with a moist (but not wet) soil mix and leave the bag in the refrigerator for about 10 to 12 weeks. When you bring the bag out of the cold, the seeds will think it’s springtime and begin to sprout.
What’s your favorite method to get seeds to germinate? Let us know in the comments below.
Links & Resources
Some product links in this guide are affiliate links. See full disclosure below.
Episode 37: Starting Seeds Indoors: The Non-Negotiables for Success, Pt. 1
Episode 38: How to Start Seeds Indoors: The Non-Negotiables for Success, Pt. 2
Episode 39: How to Start Seeds Indoors: Digging Deeper, Pt. 3
Episode 125: Saving Seeds: The Basics, the Benefits and Beyond
joegardener blog: The Best Soil Temperature for Seed Germination
joegardener Online Gardening Academy™: Three popular courses on gardening fundamentals; managing pests, diseases & weeds; and seed starting!
joegardener Online Gardening Academy Master Seed Starting: Everything you need to know to start your own plants from seed — indoors and out.
Corona® Tools – Video sponsor and Brand Partner of joegardener.com
*Disclosure: Some product links in this guide are affiliate links, which means we would get a commission if you purchase. However, none of the prices of these resources have been increased to compensate us. None of the items included in this list have any bearing on any compensation being an influencing factor on their inclusion here. The selection of all items featured in this post and podcast were based solely on merit and in no way influenced by any affiliate or financial incentive, or contractual relationship. At the time of this writing, Joe Lamp’l has professional relationships with the following companies who may have products included in this post and podcast: Rain Bird, Corona Tools, Milorganite, Soil3, Exmark, and Wild Alaskan Seafood Box. These companies are either Brand Partners of joegardener.com and/or advertise on our website. However, we receive no additional compensation from the sales or promotion of their product through this guide. The inclusion of any products mentioned within this post is entirely independent and exclusive of any relationship.