High Tunnel Bell Pepper Research 2016

  • Steve Bogash, Vegetable Crop Advisor

Producing fully colored bell peppers in the field can be a challenge due to diseases aggravated by weather conditions.  Weather often causes fruit rots just as the peppers begin to reach full color.  The simple practice of growing peppers in a high tunnel is often enough to “flip the script”, resulting in beautiful red, yellow, and orange peppers and reducing cull rates to single digits.

If possible, adding heat and environmental controls will significantly speed up maturation so that beautiful green bells are also available to market much sooner, and at better prices field grown green bells.  Once your field peppers have large green peppers, then you can continue to grow under cover for the colored markets.

During the 2016 season, we observed results from foliar nutrient applications on two popular red to green pepper varieties, Revolution and Vanguard.  We chose these varieties as they had proven themselves in earlier studies to produce consistently good color at full maturity and were often among the highest yielding in other studies.  The project was conducted using one of the high tunnels at the Penn State Southeast Research and Extension Center.  The high tunnel used was under construction in the spring of 2016, so planting date was delayed until May 15.

The objective was to see what impact specific regularly applied foliar nutrient materials would have in a program specifically focused on the production of colored bell peppers.  We collected data as to size (measured by weight), and yields of #1, #2 and culls.

The treatments below were applied every 10 days beginning four weeks after transplanting:

  • SiGuard at 5 ml (1 tsp.) per gallon
  • SiMag 58 at 5 ml per gallon
  • 4-18-38 at 15 ml (1 tbls) per gallon
  • Water only control

Each plot consisted of 12 plants and each treatment was replicated 3 times.  The plants were 18” apart in row and each bed had two rows.  The plants were supported using a box trellis system.  While there was little difference between the varieties throughout the season, the data is presented by variety in separate tables.  The data has been extrapolated to reflect yields based on 100 plants to make it easier to compare with actual grower situations.

Fertigated nutrient program was based on the ISP indoor peppers crop sheet, and tissue tests during the season showed consistently good nutrition levels.  The only insect damage noted during production and harvest was due to European Corn Borer, but this was relatively minor.  Disease management was Regalia + Badge (copper) alternated with Actinovate AG + MetaboliK HV-1 every 5-7 days.

Revolution (per 100 plants):

Foliar Treatment #1 Fruit Count #1 Fruit Wt. (lbs.) Ave. Fruit Wt. (lbs.) #2 Fruit Count #2 Fruit Wt. (lbs.) Cull Wt. (lbs.) Marketable #1 + #2 Wt. (lbs.) +/- Lbs. to Control % to Control
SiGuard 1,335 1,110 .83 138 118 88 1,1228 +290 130.92%
SiMag 58 1,470 1,170 .80 150 120 84 1,290 +352 137.53%
4-18-38 1,499 1,235 .82 148 112 78 1,347 +409 143.60%
Control 1,147 860 .75 92 78 148 938

Vanguard (per 100 plants):

Foliar Treatment #1 Fruit Count #1 Fruit Wt. (lbs.) Ave. Fruit Wt. (lbs.) #2 Fruit Count #2 Fruit Wt. (lbs.) Cull Wt. (lbs.) Marketable #1 + #2 Wt. (lbs.) +/- Lbs. to Control % to Control
SiGuard 1,563 1,188 .76 360 478 195 1,666 +289 120.99%
SiMag 58 1,573 1,196 .76 348 504 170 1,700 +323 123.46%
4-18-38 1,600 1,248 .78 320 544 168 1,792 +415 130.14%
Control 1,400 952 .68 346 425 212 1,377


In both Revolution and Vanguard all of the foliar treatments produced consistently higher fruit counts, heavier fruit weight, and an increase in the number of #1 fruit and overall marketable yields.  All of the treatments resulted in a significant increase when compared to the control.  The trend with both varieties was that the 4-18-38 had the highest yield, SiMag 58 the second highest, and SiGuard the 3rd highest.  In retrospect it would be interesting to have the 4-18-38 coupled with one of the silicon products.  The vast majority of the #2 fruit in all treatments were misshapen, but had no or very minimal scarring on the fruit itself.  Culled fruit had rots, insect damage, or surface scars that would render them unmarketable, although some could have been used for chunking/processing.

Leave a Comment