Extension Master GardenerSM Volunteers of Buncombe County

tomatoes

Online Seminar: Tomato Problems, Diseases, and Pests, July 16

Gardening in the Mountains presents:
Tomato Problems, Diseases, and Pests

Tomato blossom end rot_Cromely_CC BY-NC-ND 2.0_Flickr
Tomato blossom end rot

Thursday, July 16, 2020
11 a.m. to 1 p.m.

Location: Virtual attendance via Zoom video and audio internet connection

Presenter: Phil Roudebush, Extension Master GardenerSM Volunteer

Program Description: Tomatoes are one of the most common vegetables found in home gardens but growing them in western North Carolina can often be challenging. Both biotic (living organisms such as bacteria, fungi, and insects) diseases and abiotic (non-living factors such as garden location, soil, moisture, and nutrition) problems can affect tomatoes at all levels of maturity. The most common problems, diseases, and pests will be discussed.

Bio: Phil brings extensive experience in maintaining large vegetable gardens, herb gardens, pumpkin patches, water gardens, and a 30-acre native grass pasture. He is a retired veterinarian and native of Indiana. Prior to moving to Asheville, he lived in Colorado, Missouri, Mississippi, and Kansas, where he served as an Extension Master Gardener in Shawnee County. Phil uses his background in the sciences and gardening know-how to help others plant and maintain successful gardens.

Registration: The talk is free, but participation is limited, and 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.

Zoom seminar access: After registration, you will receive an email with instructions and a link to join this online live broadcast via Zoom. The ability to access Zoom through a computer, tablet, or smartphone with a reliable internet connection is necessary to attend.

Warm Season Vegetables: Just Because They Are for Sale Does NOT Mean it is Time to Plant Them!

In late April, walking through the garden section of many stores you’ll see tomato, pepper, squash, and cucumber plants for sale. Does this mean it is safe to plant them now?

Freeze Dates: Data on last spring freeze dates in Western North Carolina are critical to the survival of the warm season plants. In this region of the state, tomatoes, peppers—and often cucumbers and squash—are grown from transplants, not direct seeding.  Immediately after planting, they are exposed to the see-sawing air temperature fluctuations that occur during this time of year.

Frosted Leaves

The dates after which there is only a 10 percent chance of a spring freeze (32° F) based on data collected by National Oceanic and Atmospheric Administration (NOAA) from 1981-2010 for selected locations in Buncombe County Western North Carolina are:

Downtown Asheville          April 27

Asheville Airport                 May 4

Fletcher                               May 7

Black Mountain                  May 11

Swannanoa                        May 12

Bent Creek                         May 13

To be safe, then, Buncombe County Extension Master GardenersSM recommend not planting these crops in the ground until Mother’s Day each year. For your specific location and the weather forecast for any particular year, you may choose to plant earlier or later!

If you do choose to transplant earlier, be prepared to provide some type of frost protection when the temperature is expected to go below 36° F.  Techniques for frost protection include covering growing beds or rows with a floating row cover (supported by stakes or wire to keep the material from directly touching the plants). Protect individual plants with plastic milk jugs with the bottoms removed, paper caps, or water-holding walls.

Floating row cover tunnel_Carol Jacobs-Carre_CC BY-NC-ND 2.0_Flickr
Floating row cover

We also recommend “hardening-off” to toughen up your plants before putting them into the ground. Gently stroking your plants a few seconds every day while they are still indoors is helpful. Starting about seven days before you intend to plant, on warm days place your transplants—while still in their growing containers—in the general vicinity of the garden in a protected area to expose them to your intended growing conditions. This is especially important for any plants grown under greenhouse conditions.  You will need to make sure they have adequate water and bring them indoors at night to ensure their survival.

Article by Bob Wardwell, Extension Master GardenerSM Volunteer

Learn more:

Hardening off

https://polk.ces.ncsu.edu/2019/03/simple-but-necessary-hardening-off-vegetable-seedlings/

Western North Carolina Planting Calendar for annual vegetables

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

US Normals Data (1981-2010) for Buncombe County Weather Stations:

https://www.ncei.noaa.gov/orders/cdo/1712624.pdf

What Can Go Wrong with Tomatoes?

What can go wrong with growing tomatoes? Almost everything! What can go right with planting tomatoes in our home gardens? Enough to keep us growing them!

Tomatoes ripening on the vine_Todd Heft_CC BY-NC 2.0_Flickr
Tomatoes ripening on the vine

What’s the problem?
Let’s face it—there are lots of challenges with homegrown tomatoes. They wilt, they spot, they crack, they dot, they blotch, they rot. Whew! The list goes on. Few vegetables—or fruits, which are what tomatoes are—are more challenging.

Helpful hints
Try following these guidelines:

  • Decide on varieties that are well-suited to our area, bred for disease resistance, and meet your eating preferences.
  • Select healthy bedding plants or start indoors from seeds 6 to 8 weeks before the expected last frost date.
  • Wait to plant until after all danger of frost has passed, usually after Mother’s Day for Buncombe County.
  • Choose a location that receives at least six hours of sun a day.
  • Plant in well-prepared soil, rich in humus, with a pH level of about 6.0 to 7.0 (find out with a soil test).
  • Maintain uniform moisture and mulch.
  • Avoid overhead watering which can promote disease.
  • Stake or cage your plants because of their vining tendencies.

What to watch for
Although there are myriad tomato problems, most are rare. Five of the most common concerns and their solutions:

  1. Bacterial spot produces small chocolate brown spots on leaves and fruit. Recommended controls are to use treated seed, apply fixed copper bactericide, avoid overhead watering, remove old plant debris, and rotate your planting area.
  2. Blossom end rot caused by calcium deficiency produces dark-brown leathery spots on the blossom end of fruit. Prevent by liming your soil (based on soil test results) and keeping your plants evenly moist—be sure to water plants during dry periods!
  3. Sunscald produces papery white areas on the side of fruit facing the sun or yellow-orange blotches at the stem end that do not ripen. Proper planting and maintenance help prevent foliage diseases that can cause leaf drop and expose fruits to too much sun.
  4. Cracks in fruit also result from an uneven moisture supply. Tomatoes may need to be watered every 2-3 days, especially in dry weather.
  5. Flea beetles produce many tiny holes in leaves. Tomatoes will tolerate a great deal of flea beetle damage, but if damage is excessive, ask about an approved pesticide.

Preventing problems
To prevent disease in future years, do not compost plant debris. Plant tomatoes in a different location at least every third year. Then, watch your tomatoes grow! If you have a bad year, don’t give up! There’s always hope for the following season.

Consider the wisdom in John Denver’s song from his 1988 album Higher Ground:

Homegrown tomatoes, homegrown tomatoes
What would life be without homegrown tomatoes?
Only two things that money can’t buy
That’s true love and homegrown tomatoes! 

Article written by Mary Alice Ramsey, Extension Master GardenerSM Volunteer.

Learn more 

Gardening in the Mountains lecture:
All Things Tomato
by Dr. Randy Gardner, Professor Emeritus, Horticultural Science, NCSU
July 19, 2018, 10 a.m. to noon
Folk Arts Center, Asheville, NC
Watch for details in early July blog announcement. 

Growing Tomatoes in the Home Garden
by NC State Extension

Late Tomato Blight Is Here
by Debbie Green, Extension Master Gardener Volunteer, July 2015

Contact Us

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

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