Extension Master GardenerSM Volunteers of Buncombe County

seeds

Planting a Seed Saving Garden, May 25

The Learning Garden presents:
Vegetable Garden Series: Planting a Seed Saving Garden

Thursday, May 25, 2023
10:00 – 11:30 a.m.

NC Cooperative Extension
Buncombe County Center
49 Mount Carmel Road
Asheville, NC 28806

Presenter: Barb Harrison, Extension Master GardenerSM Volunteer

Planting a seed-saving garden takes careful and thoughtful planning in order to grow a garden that produces homegrown produce, but also produces viable seeds for you to harvest and save for replanting next year. There are several “rules of thumb” to remember as you choose the plants from which you will be saving seeds.

The program will begin indoors where we will cover what you need to know to have a seed-saving garden. The terms open-pollinated (heirloom), hybrid, self-pollinating, and Isolation distances are all important terms to understand for seed saving. Tomatoes, pole beans, peppers and lettuce are good choices for beginning seed saving.  We will plant these in The Learning Garden during this program. Then at the OctoberFest, on October 14th, we will harvest and save the seeds from these plants.

This will be an in-person program at the Extension office at the address above. Portions of this program may be held outside; please dress appropriately for the weather. The classroom size is limited so register to reserve your seat!

Registration: The talk is free but registration is required. Please click on the link below to register. If you encounter problems registering or if you have questions, call 828-255-5522.

Register on Eventbrite

Soil Temperature: Know Before You Plant

This time of year I get anxious to plant my vegetable garden. I look out at the sunny days and think that I should be working in my plot; but sunny, warm days can be deceiving! I need to take a step back and consider other important environmental factors before I begin.

Soil temperature is probably the most critical indicator of when to plant. I have found out the hard way that seeds do not germinate—and transplants won’t grow—if I plant when the soil is too cold.  A soil thermometer is now an essential component in my gardening toolbox.

Soil Thermometer

Factors that affect soil temperature measurement:

Time of day

  • Soil temperatures tend to be coolest between 6 and 8 a.m. in the morning, so use temperatures at this time as a guide as for planting early season crops.
  • In the heat of summer, soil temperatures are highest between 3 and 5 p.m., so use temperatures at this time as a guide for planting late season crops.

Depth of thermometer

  • Take soil readings for seeds at a depth of 1 to 2 inches.
  • Take soil readings for transplants at a depth of 4 to 6 inches.

How to measure soil temperature:

  • Push the thermometer into the soil to the depth of planting.
  • In dense soil, you can use a screwdriver to make an initial hole to the right depth to avoid bending your thermometer.
  • Follow the directions that came with the thermometer as to how long to leave the thermometer in the soil to get an accurate reading.
  • Record the temperature and then move it to another part of the garden.
  • Record measurements from 3 to 4 different places in your planting plot.
  • Take soil temperatures daily for a few days and average the temperatures to be sure your soil is the right temperature for planting

Soil temperatures vary for each type of vegetable plant!

Greens_Billtacular_CC BY-NC-ND 2.0_Flickr
Arugala and mixed lettuces

A list of soil temperature data for some vegetable seeds’ germination:

  • Lettuce: minimum 32℉; optimum range 60 to 75℉
  • Peas: minimum 40℉; optimum range 65 to 75℉
  • Snap beans: minimum 60℉; optimum range 75 to 85℉
  • Pumpkins: minimum 60℉; optimum range 85 to 95 ℉

If you check the soil temperature rather than the air temperature or only the calendar date, you can increase your chance of your seeds sprouting and thriving!

Article by Bob Wardwell, Extension Master GardenerSM Volunteer

Interactive Soil Temperature Map for North Carolina: https://climate.ncsu.edu/map/

Soil Temperature Conditions for Vegetable Seed Germination:

https://sacmg.ucanr.edu/files/164220.pdf

Range of possible planting dates: https://content.ces.ncsu.edu/western-north-carolina-planting-calendar-for-annual-vegetables-fruits-and-herbs

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

 

Contact Us

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

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