Pepper

Introduction

Pepper (Capsicum annuum, C. chinense; Family Solanaceae) is a warm-season crop requiring 3-4 months of frost-free growing days. It is started from transplants. Bell peppers are the most commonly grown and are usually harvested green. Fruits left to mature on the plant turn red, orange or yellow, and sugar content increases markedly. Other types of sweet and chili (hot or pungent) peppers are usually elongated and tapered. Varieties grown for green peppers take 55-60 days from transplanting to begin producing fruit; colored fruit takes approximately another 20 days to develop. Hot peppers generally become more pungent as they mature or if grown under stress. Check variety descriptions carefully to obtain the proper peppers for your markets.

Types and Varieties

Pepper Varieties
Field Sweet Bell - Green to Red Hot - Ancho/Poblano
Captain - BLS0-10, P Bastan - TMV
King Arthur - BLS2, PVY, ToMV Baron - BLS123
New Ace - TMV Trident - TMV
Nitro S-10 - BLS0-10, TMV, P, TSWV  
Olympus - BLS123 Hot - Anaheim
Paladin - BLS123, P, TMV, TEV Charger - TSWV
X3R Red Knight - BLS123, PVY Numex Joe E. Parker
Sailfish - BLS123, TMV, P  
Tarpon - BLS0-10, P, TMV Hot - Jalapeno
Turnpike - BLS0-5,7-9, P, TMV Evermand - BLS123
  Jalafuego - BLS12378, PVY
Field Sweet Bell - Specialty Colors Jedi - BLS123
Delirio (orange) - TMV, TSWV Orizaba - BLS123
Flavorburst (yellow)  
Islander (purple to red) - TMV Specialty Hot
  Numex Suave Orange (mild orange habanero)
Greenhouse Sweet Bell Hungarian Yellow/Hot Wax
Abay (yellow) - BLS12345  
Brocanto (yellow) - TMV, TSWV Specialty Sweet
Milena (orange) - PVY, TMV, TSWV, TEV Carmen (frying/Italian, red)
Sprinter (red) - TMV Escamillo (frying/Italian, orange)
  Habanada (mild orange habanero)
Resistant or tolerant to: BLS: Bacterial Leaf Spot (races indicated); CMV: Cucumber mosaic virus, P: Phytophthora crown rot, PVY: Potato virus Y, TEV: Tobacco etch virus, TMV: Tobacco mosaic virus, ToMV: Tomato mosaic virus.

Soil Fertility

Apply lime according to soil test results to maintain soil pH at 6.5-6.8. Sidedress nitrogen can also be applied through a drip irrigation system over the course of the remainder of the season. This is particularly advantageous in soils prone to leaching. See Fertigation for more information. Excess nitrogen has been shown to cause excessive vegetative growth and reduce yields. A pre-sidedress nitrate test (PSNT) can advise on the need for sidedress nitrogen. High P starter fertilizer can be used at transplanting, especially with cool soil conditions.

Less nitrogen fertilizer will be needed if legume sod was plowed down or if manure was applied (see Table 1 and Table 7).

PLANT NUTRIENT RECOMMENDATION ACCORDING TO SOIL TEST RESULTS FOR PEPPER
PEPPER NITROGEN (N) LBS PER ACRE PHOSPHORUS (P) LBS P2O5 PER ACRE    POTASSIUM (K) LBS K2O      PER ACRE
SOIL TEST RESULTS   VERY LOW LOW OPTIMUM ABOVE OPTIMUM VERY LOW LOW OPTIMUM ABOVE OPTIMUM
Broadcast/Planter
50
150
100
25-50
0
200
150
50
0
Sidedress 2-3 Weeks after Planting
50
0
0
0
0
0
0
0
0
Sidedress after First Fruit Set
40
0
0
0
0
0
0
0
0
TOTAL RECOMMENDED 140 150 100 25-50 0 200 150 50 0

Planting

Growers should produce their own transplants or contract with a reputable local supplier to minimize the potential of importing severe disease and insect problems that are common in other regions. Sow seeds 8 weeks before field transplanting. Peppers are a slow-growing crop and need protection from soil-borne diseases, especially damping-off organisms. Use seed treated with a suitable fungicide or use a biofungicide soil drench (See Table 24, Biological Disease Control Products in the Biorational and Organic Pesticides).  Avoid over-watering. Avoid contamination from the greenhouse floor by lining it with plastic, growing plants on benches, and hanging watering devices when not in use. Do not permit moisture to remain on seedlings for more than 2-3 hours after watering. This may require adjusting watering rates on cloudy days.

One ounce of seed will produce 3,000-5,000 plants. About 8,000-14,500 plants are required per acre, depending on your choice of spacing in the field. Seeds may be sown thickly in flats and later transferred to 72-cell trays. Peppers thrive under warm conditions; seeds germinate best at 85-90ºF, and seedlings develop well at 75ºF during the day and 65ºF at night. Peppers are susceptible to transplant shock. Reduce temperature and water and increase air movement around the plants to condition them for transplanting. A precaution: overly-hardened plants are slow to recover and yields may be reduced. Plants should be set in the field after the danger of frost is over, and the soil temperature is at least 60ºF.

Field Culture

Peppers are commonly grown on black plastic mulch with drip irrigation in the Northeast. Planting into raised beds, especially in heavy or poorly drained soils, can also help prevent root rot diseases. When transplanting into black plastic mulch, center the transplants in holes to avoid burning stems and damaging or killing seedlings as plastic heats up. For best results, 4-8" tall plants should be transplanted on a cloudy, calm day, preferably in the late afternoon.

Space transplants 12-18 in. apart within rows (67-100 plants per 100 feet of row) and 3-3.5 feet between rows. With double rows on plastic, set each row as far apart as the plastic permits, but remember that plants can tip outward (lodge), bringing fruits in contact with bare soil. This spacing requires 8,300-14,500 plants per acre.   

Some smaller pepper varieties produce spindly seedlings and plants that are not as sturdy as bell peppers and can lodge much more readily. Transplanting the seedling so that the cotyledons are at the soil surface (the root ball will be approximately 2 in. deep) will significantly decrease lodging without adversely affecting yield. 

Peppers may require staking to minimize lodging and sunscald. In each row of plants, drive half a tomato stake (18-24 in. long), 6 in. into the soil between every 4-10 plants. Tie polyethylene strings at 8-16 in. heights as plants grow. Run string from stake to stake; first down one side of the plants, looping and tightening it around each stake, and then back on the opposite side of the plants. Leave a 3 ft. gap in the trellis system every 50-100 ft. to facilitate harvesting. In windy locations, it may be helpful to erect temporary windbreaks such as snow fence. Some growers have found improved production with such windbreaks in place.

Research in the Northeast has shown that pruning peppers is not profitable.

High Tunnel Production

Production of peppers in high tunnels has gained popularity in recent years. High tunnel peppers can produce higher yields than field peppers, and while they deliver less revenue than high tunnel tomatoes, they also require significantly less labor because they do not need to be pruned. Quality of colored bell peppers is often higher in high tunnels than in field production. Similarly to field peppers, high tunnel peppers are grown on black plastic with drip irrigation and are planted in single or double rows, 12-18 in. apart. Some varieties are marketed as being for high tunnel production, but may only reach their full yield potentials with pruning, supplemental heat, and long seasons; field varieties have performed as well or better than high tunnel varieties in high tunnels in university trials. Trellising is a common practice in high tunnel peppers—in this protected environment, one string can be run along each side of a double-row bed, with stakes on either side of the bed (as opposed to running one string along both sides of each row as is common in tomatoes).

Harvest and Storage

Green bell peppers normally are harvested in the green (immature) stage after the fruits have reached full size and the walls are firm and have thickened. Colored bell peppers take several additional weeks to turn color. Harvest the crop twice a week to achieve maximum yields, or every 7-10 days for maximum size. Peppers are picked by a twisting, pulling motion with part of the stem adhering to the fruit. Branches can break easily during harvest. Teaching workers the proper harvest technique can help avoid plant breakage and lodging, and extensive losses due to sunscald.

Peppers can be brushed or washed before packing. If peppers are washed, wash water temperature should be as warm or slightly warmer than that of the peppers. Cold wash water reduces the temperature of the pepper and that of the air inside the fruit cavity. This creates a partial vacuum, which draws some of the wash water (and any bacteria that may be in the water) into the fruit. There are commercial sanitizers registered for use in wash water to help prevent bacterial contamination through infiltration and control postharvest rots.

Containers used are wire-bound crates, cardboard boxes, and bushel baskets. Twenty-four pounds per container is an average weight. The wholesale market prefers large peppers (75 or less in a 1 1/9 bu. box).

Optimal storage conditions are 45-50°F and 85-90% relative humidity. Chilling injury will occur below 45°F, but may not become apparent until the fruit have been brought back to room temperature.