germination – My Chicago Botanic Garden

Students in the Chicago Botanic Garden and Northwestern University Program in Plant Biology and Conservation were given a challenge: Write a short, clear explanation of a scientific concept that can be easily understood by non-scientists. Each week this spring, we’ll publish some of the results.

These brief explanations cover the topics of seed dormancy and germination, the role of fire in maintaining prairies, the evolution of roots, the Janzen-Connell model of tropical forest diversity, and more. Join us the next several weeks to see how our students met this challenge, and learn a bit of plant science too.

Alexandra Seglias is a second-year master’s student in the Plant Biology and Conservation program at Northwestern University/The Chicago Botanic Garden. Her research focuses on the relationship between climate and dormancy and germination of Colorado Plateau native forb species. She hopes that the results of her research will help inform seed sourcing decisions in restoration projects.

PHOTO: A tiny oak sprouting from an acorn. — A tiny oak emerges from an acorn. Photo by Amphis (Own work) [CC BY-SA 3.0], via Wikimedia Commons

Dormancy and Germination

The seed is an essential life stage of a plant. Without seeds, flowers and trees would not exist. However, a seed doesn’t always live a nice, cozy life in the soil, and go on to produce a mature, healthy plant. Similar to Goldilocks, the conditions for growth of a seed should be “just right.” The charismatic acorn is just one type of seed, but it can be used here as an example. Mature acorns fall from the branches of a majestic oak and land on the ground below the mother tree. A thrifty squirrel may harvest one of these acorns and stash it away for safekeeping to eat as a snack at a later time. The squirrel, scatterbrained as he is, forgets many of his secret hiding places for his nuts, and the acorn has a chance at life. But it’s not quite smooth sailing from here for that little acorn.

Imagine trying to be your most productive in extreme drought, or during a blizzard. It would be impossible! Just as we have trouble in such inhospitable conditions, a seed also finds difficulty in remaining active, and as a result, it essentially goes into hibernation until conditions for growth are more suitable. Think of a bear going into hibernation as a way to explore seed dormancy. The acorn cozies up in the soil similar to the way a bear crawls into her den in the snowy winter and goes to sleep until spring comes along. As the snow melts, the bear stretches out her sore limbs and makes her way out into the bright world. The acorn feels just as good when that warmer weather comes about, and it too stretches. But rather than limbs, it stretches its fragile root out into the soil and begins the process of germination. This process allows the seed to develop into a tiny seedling — and perhaps eventually grow into a beautiful, magnificent oak tree.

Our scientists are studying seed germination in a changing climate. Learn how you can help efforts to help match plants to a changing ecosystem with the National Seed Strategy.

Anticipation is running high for Seed Swap!

PHOTO: A dried sunflower head. — Panache sunflower (*Helianthus annuus* ‘Panache’) shown in its native seed packet.

It’s always a fun day with a community vibe, as Chicago area gardeners gather to swap seeds, stories, and green-thumb tips. A special bonus of 2014: keynote speaker Ken Greene (founder of the terrific Hudson Valley Seed Library) will be available during the swap to answer questions and offer “sage” seed-starting advice.

With that in mind, here are five simple secrets for seed-starting success:

1. Quality seed starter. Give your seeds a healthy jump start by planting them in a really good seed starting mix. Don’t skimp on quality here—plants grown in inferior mix will never perform like those grown in a high-quality medium. Some adjectives that should describe the product you buy: sterile, fine-grained, free-draining, fluffy, uniform. One brand we’ve had success with: Black Gold.

2. The back of the pack. It’s a simple step that can make a big difference: read the back of the seed packet before you sow. It’s full of important and helpful information—often spelled out in great detail—such as planting depth, days to germination, and watering requirements. Save the seed packs after you sow, too, since there’s often valuable transplant and harvest info there as well.

3. D.I.Y. pots. You don’t need a fancy setup to start seeds. D.I.Y.ers can make their own paper pots; recyclers can put egg cartons to good second use; and the organically minded can replace plastic with peat or compost pots that go straight into the ground and disintegrate as the season progresses. Reusing last year’s plastic pots? Wash them out thoroughly and rinse in a 10 percent bleach solution to knock out fungus and residues before filling with starting mix.

4. The right light. A strong light source is crucial for stimulating plant growth. Without it, plants turn leggy, making them weak and more susceptible to breakage. Consider full southern window exposure as a mere starting point—even better is a grow light that can be raised with the plant’s height, while offering the 12 full hours of strong, even light that seedlings need.

PHOTO: Bean sprouts. — Beans sprouted in dampened paper towel.

5. Self-watering system. Started seeds in years past, only to have them dry out and wither before you know it? You may be a candidate for a simple capillary mat/self-watering system. After filling pots with seed starting mix, set them on the specially-designed mat/tray—fill the tray with water, which the mat draws up to the pots, keeping them properly moist without being waterlogged. The system is a boon to those who can’t water every day; an optional lid helps keep humidity high. They’re available at many nurseries and online.

At Seed Swap, Garden experts and master gardeners from our Plant Information Service desk will be available to chat, but we’ve found that the best way to get an answer is also the simplest and most satisfying: turn and ask the gardener next to you.

Looking forward to seeing you at the swap!

Tag: germination

60-Second Science: Dormancy and Germination

Five Seed-Starting Secrets