Roanoke Times
Copyright (c) 1995, Landmark Communications, Inc.
DATE: THURSDAY, July 27, 1995 TAG: 9507270031
SECTION: CURRENT PAGE: NRV-5 EDITION: NEW RIVER VALLEY
SOURCE: JOE HUNNINGS
DATELINE: LENGTH: Medium
Whether hot chilis or sweet bells, peppers are of interest to consumers, gardeners and researchers throughout the country. Here is a brief summary of pepper research:
Most of us have heard of the advantages (increased yield, better emergence, insect control) of row covers for many crops. A study at the University of Illinois found that five weeks under row covers from transplanting time produced the highest early and total yield when compared to one to seven weeks under cover. The conditions will vary in home gardens, but the message remains - use row covers for a few weeks to get your pepper plants going, then remove the covers to get optimal yield.
The size of the transplant may affect early yield, but it probably won't affect the total yield. In comparisons of 60-day-old transplants grown in relatively large (approximately 2-by-2-by-21/2 inch) containers to younger (30-, 40-, or 50-day-old) transplants, researchers found that the older, larger transplants produced greater early yield, but similar total yield.
If you have limited indoor growing space, you can start your pepper transplants relatively late (four to six weeks before transplanting) and still get good results. If you can't wait for the first pepper, go ahead and start early, and give your plants lots of room.
Have you heard of mycorrhizal fungi? Lots of researchers have, and they have found that these microscopic organisms that inhabit plant roots can be beneficial. In particular, vascular-arbuscular mycorrhizal fungi (VAMF) increase yield in peppers grown in low-phosphorous or low-moisture soils. They probably increase either phosphorous or moisture uptake, or both. The plants are inoculated with VAMF at transplanting.
When should you fertilize your peppers? Take your choice - either before planting or throughout the growing season. Little or no difference in yield was seen in a study that compared the effects of slow-release fertilizer applied before planting to soluble nitrogen fertilizer applied several times throughout the season.
Planting one pepper plant to a hill will get you the most peppers per plant, but for the most peppers per total garden area, go ahead and crowd in the plants. A study on pepper spacing found the largest yield coming from plots planted with peppers two per hill and only 10 inches apart in rows 18 inches apart.
In Florida, where this research was done, pepper fruit size remained constant. Here in Virginia, fruit size has been found to decline when plants are crowded, so you may want to experiment with closely spacing only part of your pepper crop and see how it works in your garden.
If a limited budget (either time or money) forces you to choose between mulching with black plastic or irrigating, choose the mulch. Combining the two will give you the greatest yield of peppers, but only 10 percent higher than mulch alone. Trickle irrigation and sprinkler irrigation performed equally well in this study, so don't feel bad if you don't have the latest in watering technology in your pepper patch.
Once you have harvested your peppers, keep them fresh and crisp longer by wrapping or bagging them in polyethylene. This prevents moisture loss and the corresponding shriveling of fruit. Peppers should be dry when wrapped and kept in a cool (50 to 65 degrees Fahrenheit) location for longest storage.
Joe Hunnings is the Virginia Cooperative Extension agent for agriculture in the Montgomery County Extension Office in Christiansburg. If you have questions, call him at 382-5790.
by CNB