Welcome to the Ultra Gro Agronomy Letter!
With this year's razor-thin margins, water issues, and growing challenges, controlling what you can is crucial in setting yourself up for success next year. That starts with establishing a solid Post-Harvest plan. If you haven't gotten with your Crop Advisor yet to take care of your Post-Harvest needs, we recommend doing so ASAP.

Naturally, the focus of this issue of the Agronomy Letter is Post-Harvest. You'll hear from Devin Clarke, Permanent Crop Manager of Yara North America, on soil and nutrition management for permanent crops during this season. Veteran Ultra Gro CCA Dustin Stewart shares his thoughts on Post-Harvest, and we're sharing a timely flyer with one approach to Post-Harvest nutrition. Finally, we're kicking off our Meet the Team series with an intro to Crop Advisor Jesse Sanchez.

If you have any questions about the information included below, feel free to give us a call. Thank you!
Post-Harvest for Permanent Crops
by Devin Clarke, Permanent Crop Manager of Yara North America
Improper management of soil moisture and nutrition post-harvest can lead to premature defoliation, impaired photosynthesis and diminished carbohydrate storage; compromising the plant’s ability to defend itself from abiotic stresses in winter and spring. 

Beyond defending the plant from heat stress and supporting healthy root development, calcium supplementation has been documented to reduce cellular ion leakage, a direct result of frost damage. This increases woody plants’ ability to withstand below freezing temperatures by increasing extracellular Ca2+ levels. This ultimately limits ice crystal formation which can compromise cell structure and lead to tissue death. 

Calcium is also responsible for the transport of K+ into guard cells to maintain optimal stomata function. Proper guard-cell function allows the plant to cool itself when necessary, pull nutrients through the transpiration stream to where they are required, and conduct photosynthesis. Healthy, vigorous trees and vines will resume photosynthesis sooner and at a more active rate following harvest. 

Photosynthesis and carbohydrate production begin with optimized stomate operation.
Carbohydrates can then move through the vascular system to where they are required
Carbohydrates are the product of photosynthesis. For most of the crop year, plants are at a carbohydrate deficit as the fruit acts as a significant sink. The period between crop maturity and leaf senescence is the only window all season, to store carbohydrates to improve plant health and productivity. Soluble carbohydrates interfere with ice crystal formation, protect cells and membranes, and reduce mechanical injury related to freezing. Both potassium and boron required for the transport of carbohydrates for use by the plant. 

Carbohydrates are the plant’s currency to defend itself from stress and to support optimal crop performance. Focus on three key areas to support optimal production and storage:

  • Proper post-harvest irrigation management
  • Do NOT overwater! This eliminates oxygen from the rootzone and will kill roots. Also assess your tree’s canopy health as the tree’s ability to effectively use water is only as good as its ability to move it through the vascular system and transpire. 

  • Support root health
  • Calcium is critical to support new developing roots. Greater root activity leads to greater soil exploration and improved access to water and nutrient resources.

  • Support vascular health
  • Proper internal water balance along with optimized levels of calcium, potassium, and boron will facilitate photosynthesis, carbohydrate production, and movement to create reserves for stress mitigation and crop productivity.

Post-Harvest Thoughts
by Dustin Stewart, CCA
Harvest is well upon us. This is always my favorite time of year. We get to see the fruits of our labor as fall finally starts to rear its head. It is also post-harvest nutrition time, aka: the last chance of the year to get our trees and vines ready for Spring 2023!

With post-harvest nutrition, our objective is twofold. On one hand, we need to revitalize our trees and vines for bud formation/retention and to store carbohydrates for next spring. We need to address any nutrient deficiencies they have and restore photosynthesis as soon as possible. They have just gone through an extremely stressful event with the heat, water stress, and crop removal. 

On the other hand, we also need to focus on corrective soil applications. We use this period to address our calcium-magnesium balance, excessive sodium levels, and any other nutrient deficiency or imbalance that we may be facing. We are all praying for rain. In the event our prayers are answered, using calcium and soil amendments to help maximize sodium-leaching potential is particularly important this year. Especially after so much well water has become the prominent source of irrigation water for so many of us.

Our best growers tend to do these applications immediately following harvest. It is important to base your nutrient applications on this season’s soil, water, and tissue analysis (July-August lab reports). 

When looking at your soil analysis, look first at your pH, your exchange capacity, and your base saturation percentages. What is your calcium to magnesium ratio? How much sodium has accumulated? How much potassium do you have? It is vital that we take a close look at these numbers and work on the greatest limiting factor first. For most of us, this is not the year fix everything on the ranch. Use your budget to prioritize your objectives and fight the fights that can be won.  

With a lack of rain and elevated material and application costs, dry broadcast nutrients may not be your best bet. We find they are not fitting into lean budgets. Consider liquid injectable fertilizers this fall. They are substantially more soluble and go through your irrigation system where your feeder roots are. They go to work immediately and are less rain-dependent than dry materials. Bottomline: in these times of “less is more”, liquid fertilizers are appreciably less expensive, easier to apply, and tend to work better than dry blends.

Work with your advisor closely this fall. Talk about nutrient solubility. Take a deep dive into your soil reports. If you don’t like where your season ended, try something different. It isn’t business as usual this year and the importance of your decisions is vital to your future success.  
Post-Harvest Flyer: The Ultra Gro Two Step
Meet the Team: Jesse Sanchez
Meet Crop Advisor Jesse Sanchez! We’re kicking off a new series of introductions to the Ultra Gro team, starting with Jesse. He's based in the Watsonville and Salinas areas, specializing in strawberries and raspberries. Check out his Q&A below, and be sure to give him a call if you’re in his neck of the woods!
Q: How long have you been with Ultra Gro? 
A: Since August of 2012.
Q: What made you want to become a Crop Advisor? 
A: To grow as an individual in what I love and help growers as best as I can.
Q: How would you describe your everyday at Ultra Gro? 
A: I’m always learning and evolving with every new year of planting, harvesting and climate change.
Q: What is your favorite thing about your work? 
A: When I am able to help my customers through challenging situations.
Q: What is your life like outside of work? 
A: Spending time with the family, hiking, fishing, camping, and golf.
Q: Most importantly, Giants or Dodgers? 
A: Giants.
Please call your Ultra Gro Crop Advisor if you have any questions.
Thank you!