Category Archives: Resources

Pre-Bloom & Bloom Nutrition and Growth Management for Apple Orchards

Posted on by

It’s a beautiful day out there, so let’s enjoy it as it is and stay positive—no need to keep checking the weather station just yet! Since most of our apple cultivars are between tight cluster and full bloom, I wanted to send a quick reminder about some important considerations for early-season nutrient and growth regulator applications during this critical stage.

Pre-Bloom Foliar Nutrient Sprays: The Nutrient Cocktail

A common and effective approach during the tight cluster to pink bud stage is to apply a foliar “nutrient cocktail” of nitrogen, boron, and zinc (if possible).
Nitrogen (Urea)
A foliar urea spray can boost nitrogen levels in developing buds and spur leaves. This helps strengthen bloom and improve early fruit set.
• Apply a low-biuret urea at 3 lb per 100 gallons of water (dilute spray). Make sure the biuret content is below 0.25% to avoid leaf damage.
• Nitrogen is vital for rapidly expanding tissues. Pre-bloom applications support both flower and shoot development.
Boron
If your boron levels were low last season or you’re looking to support flower fertility, now is the time.
• Apply a spray-grade boron product (e.g., Solubor®) at 1 lb per 100 gal (~0.2 lb actual B).
• Boron is essential for pollen viability and pollen tube growth. Even mild deficiencies can reduce fruit set.
Zinc
Zinc deficiency is fairly common, especially in certain soils and older blocks.
• Include zinc EDTA chelate at label rate in your foliar spray. Avoid zinc sulfate at this timing if frost or oil applications are nearby, as it can cause tissue damage.
• Zinc plays a key role in enzyme activation and pollen formation. Early sprays ensure flowers and young leaves develop properly.
Pro Tip: Tank-mix this nutrient spray with early-season fungicides but always check for compatibility.

Bloom-Time Nutrient Applications

Boron at Bloom
A repeat boron application at pink or full bloom supports fertilization and early fruit development.
• Apply 2.5–5 lb/acre of Solubor (equivalent to 0.5–1.0 lb of actual B).
• This timing helps secure pollen germination and supports calcium movement into developing fruit. Just be careful not to overdose.
Early Calcium Sprays
Calcium uptake is critical in the early weeks after bloom, especially for sensitive varieties like Honeycrisp.
• What to do: Begin foliar calcium applications at pink or early bloom, and continue through the early cover sprays.
• Rates: Use 2–4 lb of calcium chloride (CaCl₂) per 100 gallons of spray. Include a non-ionic surfactant and apply during fast-drying conditions to avoid leaf burn.
• Why it matters: Calcium builds strong fruit cells and reduces the risk of bitter pit and other disorders. Early sprays are particularly effective.
• Spray safety: Avoid mixing calcium sprays with Apogee or Kudos.
Foliar Urea at Bloom
Foliar nitrogen can give your fruit set a helpful boost during bloom, especially if your trees are weak or suffered frost damage.
• What to do: Apply 3 lb of urea per 100 gal at bloom, and 5–6 lb per 100 gal at petal fall.
• Why it matters: Urea helps prolong flower viability and encourages strong fruit development. It supports cell division in young fruit, improving size at harvest.
• Caution: Avoid using foliar urea beyond the second cover spray — late-season nitrogen can hurt color development.
Prohexadione-Calcium (Apogee® or Kudos®): Managing Tree Growth
When applied at the right time, prohexadione-calcium helps you control excessive shoot growth, open up your canopy, and even reduce fire blight risk — all while improving fruit calcium allocation.
Application Timing
• When to apply: At the pink bud stage, or early bloom at the latest, when shoots are 1–3 inches long.
• Split plan: Apply 6 oz/acre at pink, and repeat in 2–3 weeks (e.g., at petal fall).
Mixing Tips
• If your water is hard, add 1–2 lb of ammonium sulfate (AMS) per 100 gal to condition it.
• Add a nonionic surfactant to improve uptake (follow label rates).
• Do not mix Apogee with calcium or boron — these reduce its effectiveness.
Honeycrisp Consideration
Apogee is especially valuable on Honeycrisp. It helps reduce the competition for calcium, lowering the risk of bitter pit. Just be sure there’s enough leaf tissue present before spraying to ensure good absorption.

Possible Tax Credits Available for Purchases of Precision Spray Equipment

Posted on by

By Mark Sutphin, Associate Extension Agent

I received a recent inquiry that I thought I would share so that all may know of the possible tax credit opportunity. Through Virginia Agricultural BMP Cost Share and Tax Credit Programs, tree fruit and grape growers who purchase precision spray equipment might be eligible for a tax credit. The specific question I received was regarding a Durand Wayland Smart Spray system, but other equipment manufacturers have systems that may be eligible for tax credits as well. Please reach out to Virginia Department of Conservation & Recreation (DCR) or your local Soil and Water Conservation office for specifics on the tax credit program and to file for approval of a tax credit claim.

The exact wording regarding precision agricultural equipment from the Program Year 2015 Virginia Agricultural Cost-Share (VACS) BMP Manual can be found below as well as the link to the entire document. Tax Credit for Purchase of Precision Agricultural Equipment (page IV – 13) § 58.1-337.

Tax credit for purchase of advanced technology pesticide and fertilizer application equipment.

A. Any individual engaged in agricultural production for market who has in place a nutrient management plan approved by the local Soil and Water Conservation District by the required tax return filing date of the individual shall be allowed a credit against the tax imposed by § 58.1-320 of an amount equaling twenty-five percent of all expenditures made by such individual for the purchase of equipment certified by the Virginia Soil and Water Conservation Board as providing more precise pesticide and fertilizer application. Virginia Polytechnic Institute and State University and Virginia State University shall provide at the request of the Virginia Soil and Water Conservation Board technical assistance in determining appropriate specifications for certified equipment, which would provide for more precise pesticide and fertilizer application to reduce the potential for adverse environmental impacts. The equipment shall be divided into the following categories:

  1. Sprayers for pesticides and liquid fertilizers;
  2. Pneumatic fertilizer applicators;
  3. Monitors, computer regulators, and height adjustable booms for sprayers and liquid fertilizer applicators;
  4. Manure applicators;
  5. Tramline adapters; and
  6. Starter fertilizer banding attachments for planters.

B. The amount of such credit shall not exceed $3,750 or the total amount of the tax imposed by this chapter, whichever is less, in the year of purchase. If the amount of such credit exceeds the taxpayer’s tax liability for such taxable year, the amount which exceeds the tax liability may be carried over for credit against the income taxes of such individual in the next five taxable years until the total amount of the tax credit has been taken.

C. For purposes of this section, the amount of any credit attributable to the purchase of equipment certified by the Virginia Soil and Water Conservation Board as providing more precise pesticide and fertilizer application by a partnership or electing small business corporation (S corporation) shall be allocated to the individual partners or shareholders in proportion to their ownership or interest in the partnership or S corporation.

http://dswcapps.dcr.virginia.gov/htdocs/agbmpman/csmanual.pdf

Additional information regarding the Virginia Agricultural BMP Cost Share and Tax Credit Programs can be found at the following link:

http://www.dcr.virginia.gov/soil_and_water/costshar.shtml

Mark Sutphin Associate Extension Agent | Agriculture and Natural Resources, Horticulture | Unit Coordinator (Frederick) Virginia Cooperative Extension – Frederick County Office | 107 North Kent Street | Winchester, VA 22601 Phone – 540.665.5699 | Fax – 540.722.8380 | Cell – 540.398.8148 | Email – mark.sutphin@vt.edu | http://offices.ext.vt.edu/frederick/ | http://vacoopext.blogspot.com/

Serving the counties of Frederick, Clarke, Page, Shenandoah, & Warren VIRGINIA POLYTECHNIC INSTITUTE AND STATE UNIVERSITY Extension is a joint program of Virginia Tech, Virginia State University, the U.S. Department of Agriculture, and state and local governments.

2015 Winter Fruit School Hard Cider and Tall Spindle Presentations

Posted on by

In response to requests for more information about my talks at the 2015 Winter Fruit Schools, I have linked condensed versions of my presentations to this blog post.

In addition, more information about hard cider can be found at:

More information about tall spindle orchards can be found at:

Gregory Michael Peck, Ph.D.
Assistant Professor of Horticulture • Virginia Tech
Alson H. Smith, Jr. Agricultural Research and Extension Center
595 Laurel Grove Road • Winchester, VA 22602 • USA
540.869.2560 X19       greg.peck@vt.edu
Tree Fruit Homepage: www.anr.ext.vt.edu/tree-fruit/

Predicted Harvest Dates for Winchester and Central Virginia

Posted on by

Predicting harvest date depends upon many factors, including full bloom date, accumulated heat units (growing degree days) over the course of the growing season, physiological stressors (e.g., disease and insect damage or drought), day to night temperature differentials as harvest approaches, and the amount of precipitation. However, the number of days between full bloom and harvest has been shown to be the most reliable predictor of harvest date.

More than two decades ago, researchers in Michigan determined that there there are an average of 143 days between full bloom and the first commercial pick of Red Delicious apples that are to be held in controlled atmosphere storage (i.e., firmness between 17-18 lbs; starch between 2.5-4 on the 8-pt scale Cornell Starch Chart). Additional seasonal adjustments above or below the average number of days until harvest are made based upon the average daily minimum temperatures for the 15 days after full bloom.

For the past several seasons I have tested the Michigan model using fruit from a block of Bisbee Red Delicious on MARK rootstock. Results to date have shown that this model is very good at predicting harvest maturity in Virginia.

Based on the Michigan model, here are the predictions for 2013:

In Winchester, Bisbee Red Delicious full bloom was April 23 and average minimum temperature for the 15 days after full bloom was 8.0°F less than 50°F. Using this data in the Michigan model, harvest is predicted ~8 days more than 143 days between full bloom and harvest. This puts the predicted harvest date for the first CA pick of Red Delicious at September 19.

In Central Virginia (Piney River), full bloom for Red Delicious was estimated to be April 20 and the predicted harvest is September 14.

Since most growers have Red Delicious trees in their orchards, other cultivars (and strains of Red Delicious that ripen earlier than Bisbee) can be estimated based upon experience on their picking date relative to Red Delicious.

Another method for estimating harvest date uses the rule-of-thumb that says, “for each 2-3 days departure for the normal bloom date, there will be a one-day departure from the normal harvest date.” (Blanpied and Silsby, 1992).

You can find more information about harvest maturity indices in a post from last year.

In the next week or two, I will start conducting maturity evaluations of fruit from the Winchester AREC and surrounding orchards.

References

Blanpied, G. and K. Silsby. 1992. Predicting Harvest Date Window for Apples. Cornell Information Bulletin 221. <<pdf>>

Beaudry, R., P. Schwallier, and M. Lennington. 1993. Apple Maturity Prediction: An Extension Tool to Aid Fruit Storage Decisions. HortTechnology 3(2): 233-239.