Multi-State Strawberry Freeze Advisory (9am, Feb. 9, 2016)
Dear Growers, Agents, Agronomists and Others
The freeze coming into our region this weekend could be very damaging to emerged flower buds. This advisory provides detailed minimum temperature information for strawberry growers in NC, VA, SC, GA and MD.
A Good Reference for making a decision about the need for row cover protection:
Fig. 1. In a dormant period, a well-hardened Chandler, or Camarosa, can handle temperatures as low as 10 F without row cover protection, and not show any injury to crown tissues. Single digits can be worrisome – in the dormant condition. However, in mid-February, strawberry plants are emerging from dormancy as days get longer and warmer. Take a close look at the photo, and note the two emerged flower buds above the pencil tip. These will likely be killed at around 18 F. Many parts of the region will be seeing temperatures at, or below 18 F this weekend. In the transition period from dormancy to new leaf growth stage, there is still considerable hardiness in flower buds, and it is definitely possible for an emerged flower bud to tolerate temperatures into mid-teens, especially if it is a recently emerged, smaller flower bud. The more advanced, “fat” flower buds are more prone to damage.
Yesterday, I included this photo from a grower in Easley, SC, that was taken LAST WEEK
Fig. 2. In this photo of Camarosa plant in Easley (Asheville-like climate), you can already see two excellent new flower buds that have emerged (photo on 2/3/16). The grower is not taking any chances, and will be re-covering before the weekend. He does not feel he can afford to lose these flower buds, and I completely support his decision to recover. His area is much like Asheville, NC, and Asheville may see a low of 11 F at weather shelter height on Valentines (they are also going to 17 F tomorrow morning, and 14 F on Wed).
So, now is the time to apply those row covers in areas where there is potential for low teens, and some growers may even wish to double-up in really cold areas and/or where they have already been using row covers this winter, and plants are more advanced.
One of the chief concerns with overwinter row covers in the Mid-South relates to how the covers “push the crop’s development in winter” and make the plants more susceptible to damage from a late winter arctic clipper like the one on tap for this Valentine’s.
Data and experience driven row cover decisions: I am not sure how much experience you have had with strawberries in the mid-South, but I have been working with this crop since 1980. In my view, growers need to be getting row covers on today to prevent the possibility of this Valentine clipper from clipping a good portion of their 2016 crop. We have already seen many blossoms lost this winter season. A row cover is the only reliable way to manage a late winter freeze of this kind. With a row cover applied at this time, a grower can protect nearly all emerged flower buds as well as make sure that no injury occurs to the non-emerged flower buds. Growers with more advanced crops, may benefit from a double cover. The second cover could go on just before the weekend. Get the first one on now.
Multi-state Freeze Advisory – AWIS Minimum Temperature Tables by State and Region
Maryland Minimum Temps Feb 9-16: MD Minimum Temps Feb 9-16
Virginia Minimum Temps Feb 9-16: VA Min Temp Table Feb 9-16
North Carolina Minimum Temps Feb 9-16: NC Minimum Temp Map Feb 9-16
South Carolina Minimum Temps Feb 9-16: SC Min Temp Table Feb 9-16
Georgia Minimum Temps Feb 9-16: GA Min Temp Table Feb 9-16
AWIS MINIMUM TEMP MAPS FOR VALENTINE’S DAY
State by State Detailed 10 DAY FORECAST
Detailed AWIS forecast for multiple locations in Maryland
Detailed AWIS forecast for multiple locations in Virginia
Detailed AWIS forecast for multiple locations in North Carolina
Minimum Temp Table: GA Min Temp Table
Detailed AWIS forecast for multiple locations in Georgia