Extension Master GardenerSM Volunteers of Buncombe County

Propagation

The New Gardening Year: Can I Use Old Seeds?

What a wonderful time of year to be a gardener! The mailbox overflows with seed catalogs showcasing what is new for 2020. I also find myself looking at the 78 seed packets I already have—most great performers from past years—and see some were “packed for use in 2015” or even earlier!

Seed Packets

It’s time to decide if you need to buy new seeds; we can plant onions and peas outdoors as early as mid-February and if you grow your own transplants, you’ll want to start planning, too! For example, tomatoes will need 4 to 6 weeks before the last frost to grow to transplant size, so you’ll need to start them indoors early to mid-April here.

Seed longevity

Must I buy seeds packed for 2020 and throw away these old favorites? Not always—many seeds are viable for years. The Chicago Botanic Garden provides some general guidelines for vegetable seeds: http://my.chicagobotanic.org/wp-content/uploads/Seed-Viability-Chart.pdf

So, for example, if you have cucumber, pumpkin, or squash seed from 2014, you might be fine, but onion, leek, parsnip, or parsley seeds from 2018 may already be worthless!

Testing seed viability

If you want to test your own seeds, Ward Upham, Kansas State Master Gardener Coordinator, suggests the following quick and easy test for each type of seed you want to test:

Place 10 seeds on a paper towel moistened with warm water and cover with a second moistened towel. Roll up the towels and place inside a plastic bag with enough holes for air exchange but not so many that the towels dry quickly. Place the bag in a warm place such as the top of a refrigerator. Remoisten towels with warm water as needed. After the first week, check for germination. Remove sprouted seed and check again after another week. Add these numbers together to determine the percent germination.

Testing Seed Viability and Germination

Planting old seed

If your old seed is still viable, you can simply plant extra seed in anticipation of lower germination rates.

Storing seed

The best places to store your seed are where it is cool and dark, such as the refrigerator or a cold basement. If you save seed from your garden, be sure the seeds are dry before you store them. For purchased seeds, keeping them with their original packets allows you to quickly determine the contents. Seal seeds in an airtight container, such as a canning jar, to prevent moisture.

Article by Bob Wardwell, Extension Master GardenerSM Volunteer

For more information:

Vegetable gardening planting times: https://extensiongardener.ces.ncsu.edu/wp-content/uploads/2016/07/NC-Vegetable-Planting-Guide-1.pdf?fwd=no

**Note: Planting times for Western North Carolina Mountains are in purple and times to harvest from seed are indicated in the left-hand column. Those with an “*” should be started indoors rather direct seeded in the garden.**

Tips for growing plants from seed:

https://content.ces.ncsu.edu/extension-gardener-handbook/13-propagation#section_heading_5129

 

Seed Starting: From Sowing Indoors to Transplanting in the Garden

Indoor Seed Starting_MelanieO_CC BY-NC-ND 2.0Are you drooling over the garden catalogs arriving daily in your mail box? Are you longing to get out into the garden? Get an early start on the season by growing your own transplants from seeds! Although this will not save you money—unless you want to grow a lot of one kind of plant—it will allow you to grow varieties not available in the garden center, or to use seeds you or friends have saved. Growing your own transplants will also give you a head start on growing plants like tomatoes that take too long from direct seeding in the garden to fruiting for our growing season.

When to begin? Timing is everything
Choose what you want to grow, then use the Extension planting calendar for Western North Carolina (see Resources below) to figure out when you need to start the seeds to have the transplants ready to put in the ground at the right time. Study your seed packets for more precise information about how long before your planting date you should start each seed type and how deep to plant them. If you don’t have seed packets, Suzanne Ashworth’s book, Seed to Seed: Seed Saving Techniques for the Vegetable Grower is one useful book for seed-starting.

Petunia seedlings_Satrina0_CC BY-NC-ND 2.0Starting the seeds
Plan to use grow lights, as even a very sunny window doesn’t give enough light to grow strong plants. (See the blog Starting Seeds Indoors: Using Grow Lights.) You can start your seeds in small cell packs, peat pots or cubes, or reuse clean plastics, such as individual yogurt containers. Make sure anything you use has holes for drainage. Start your seeds in a sterile commercial mix, that does NOT contain fertilizer. Plants don’t need fertilizer until they have their first true leaves! To grow the strongest plants, move seedlings to a pot one size larger once they are established and growing steadily.

outdoorsinmay_ethnobot_CC BY-NC 2.0Hardening off the seedlings
Before planting seedlings in the garden, they need “hardening off” to prepare them for tougher outdoor conditions. Don’t try to rush the season for tender plants or a late freeze may ruin all your hard work! A week or so before you’re ready to plant, start putting your seedlings outside in a shady place during the day. Be sure to keep them well-watered and out of strong winds. Bring them in at night. After a few days of this, if night temperatures are above 45°F, you can leave them out to get them used to more sun and gentle breezes.

 Last step: planting in the garden
Ideally, put your plants in the ground on a cloudy day, or after the hottest part of the day. Water about an hour before planting and then again when they are in the ground. Make sure peat pots or cubes are thoroughly soaked and completely underground so they don’t wick water away from the plant.

Article written by Joyce Weinberg, Extension Master Gardener Volunteer.

Resources
https://content.ces.ncsu.edu/western-north-carolina-planting-calendar-for-annual-vegetables-fruits-and-herbs
https://content.ces.ncsu.edu/starting-plants-from-seeds

Starting Seeds Indoors: Using Grow Lights

This time of year, gardeners are often a bit itchy to get going! One way to partially alleviate that itch is to inventory your tools and review your gardening practices. So, let’s look at seed-starting and review the basics of indoor lighting.

GOPR1261_jalexartis_CC BY-NC-ND 2.0_Flickr
Plant seedlings under grow light

The light plants need
Plants use almost the entire spectrum of the sun’s light, so once they germinate, seedlings are much affected by the kind of light they receive. Most important are the ultraviolet range at the low end of the spectrum and the infrared portion at the upper end. The blue part of the spectrum encourages leafy growth, while the red seems to affect stem growth, budding, or flowering. In other words, blue light serves as the seedlings’ nitrogen, and red as their phosphorus, affecting the development of flower and fruit production of the adult plant.

Artificial light
Fluorescent light bulbs, unlike traditional incandescent bulbs, provide red and blue light without producing much heat. Fluorescent “grow lamps” provide an even better balance of light at both ends of the spectrum.

Remember that fluorescent bulbs also produce some heat, so you need to adjust their height above the plants. You can establish the best distance by holding your hand above the plants and adjusting the bulb’s distance to a “just right” feel.

Another thing to keep in mind: long fluorescent bulbs produce more light at their center than closer to the ends. If plants are to remain under lights for any length of time, switch them around to even out their exposure so they don’t get “leggy.” Consider more expensive LED lights if you intend to grow plants indoors long-term.

Damping off
Another cause of sickly seedlings is “damping off,” a fungal disease that will rot the lower stem and/or roots. Reduce the risk of disease by using fresh or sterilized potting soil, decontaminating pots and flats with a bleach solution, and careful watering. As with adult plants, when you water, don’t just sprinkle those plants, water thoroughly and then let the soil dry out a bit before watering again. 

Article written by Glenn Palmer, Extension Master Gardener Volunteer.

Resources:
http://butler.osu.edu/news/are-all-grow-lights-created-equal

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Buncombe County Extension Office
49 Mount Carmel Road
Asheville, NC 28806
Helpline 828-255-5522

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