Superior Sprouting: Seed Germination Essentials, Tips, and Tricks

Seeds want to grow, so give them the right preparation, conditions, and care, and you’ll be on your way to a bountiful garden

Get a jump on the growing season by starting your seeds indoors. Juver/Shutterstock

Growing plants from seeds is budget-friendly, allows you to select from more varieties than just those available at the local garden center, and lets you get a jump on the growing season.

By following a few simple rules, you’ll significantly improve your germination rate—starting with quality, fresh seeds. While many people save leftover seeds from a prior year and some properly stored seeds have been known to sprout at 3 to 5 years old and more, you’ll get the best germination rates and the healthiest plants from new stock.

Insider’s Guide

Seed packets are more than just the pretty photo on the front; they’re a comprehensive guide to the future fruits, vegetables, or flowers contained inside. They offer essential information on hardiness zones (make sure you know yours), to let you know if it will or won’t grow in your area, as well as when to plant, the planting depth, seed spacing, and sun/shade requirements.

The packet may also contain “thin to” information. Some seeds will be duds no matter what you do, so you always want to plant more than you need, allowing the removal, or “thinning,” of some seedlings that have grown too close together.

And let’s not forget the two fun days we all look forward to: days to germination (sometimes called “days to emerge”) and days to maturity, also known as harvest time! Depending on the plant, you may find additional growing tips as well. Read it all carefully to make the best plant choices and achieve the best results.

Germinating seeds on a damp paper towel is cleaner and up to three times faster than soil. ThamKC/Shutterstock

How Germination Works

The entire process starts when the seed is given water. This wakes it up by rinsing off any natural inhibitors on the surface that keep it asleep until the proper time, softens its outer layer, and hydrates the “plant food” stored inside. Keep the seeds moist, but don’t drown them. Overwatering and underwatering are two common reasons new gardeners run into problems with germination.

The second requirement is the proper temperature. While different seeds have different sprouting temperatures, ranging from 45 to 85 degrees F, most will sprout happily in the 60- to 70-degree range. This works for planting after the last frost or getting a jump on the growing season by starting plants indoors.

Light is also a consideration. While most seeds are good-natured and will sprout in light or darkness, some small seeds require light, while others require darkness. The rule of thumb is to plant the seed twice as deep as its height.

Growing Medium

While seeds grow in just about any soil in nature, to increase your germination rate, use a potting soil made for growing seedlings. This lessens the chance of early problems, such as damping off, a fungus that attacks seedlings at the base.

Some gardeners take things one step further and opt for a clean, sterile seed starting mix made of peat or coconut coir, then transplant the seedlings into potting soil after they get their first set of “real leaves.” The initial leaves, called “seed leaves” or “cotyledons,” come directly from the seed and act as a food reserve for the tiny plant. They’re generically round or oblong, while the first true leaves will look like the leaves you’ll see on the final plant.

Soil-free Sprouting

Another popular way to germinate seeds is with a paper towel. It’s cleaner and up to three times faster than soil, and you’ll know when you put the sprouted seeds in soil that they’re viable. You can also use this to test the germination rate of a packet of seeds, particularly an older one, before putting the rest in soil.

Dampen or spray the paper towel so that it’s wet but not dripping. Space the seeds out evenly on it, fold the paper towel over the seeds, and put them in a Ziploc baggie with a little bit of air inside. Place it somewhere warm—on top of a refrigerator is a popular spot—to create a mini greenhouse environment. Never put it in sunlight, as this can “cook” the seeds. Check daily to make sure the paper towel is still moist and inspect for any germination. As soon as roots appear, plant them in soil before they start rooting into the paper towel.

Now's the time to start your late-season crops for a fall harvest. FootMade0525/Shutterstock

Autumn Harvest

Feeling inspired? It’s not too late, even if you live up north. Leafy greens, root vegetables, cabbage, broccoli, and kale will grow in the cooler, shorter days of fall. Start your late-season crop seeds now.

Seed Speed

Want your seeds to germinate as soon as possible? Soak them first for 12 to 24 hours to expose the embryo to moisture and kickstart the process, and try these tried and true pointers.

Skillful Scarification

Carefully abrade tough, heavy, waterproof seed coats, such as beans, peas, and squash seeds, with a knife or sandpaper to allow more moisture to reach the embryo. Use the seeds immediately; don’t save them for later, as the nicks can cause the seed to dry out and lose viability.

Humidity Domes

Save your next plastic takeout container. Punch holes in the bottom and you have a convenient seed tray, while the clear lid creates a terrarium effect. Or you could cut a two-liter bottle into a humidity dome for seeds planted in a traditional pot.

Seed Tubes

Plant seeds in paper towels or toilet paper rolls. Simply cut them to two-inch lengths, place them in a plastic container, and fill them with soil. When you’re ready, transplant them, rolls and all. This is particularly useful for plants that don’t like to have their roots jostled.