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Ornamental Pepper

Series: Explosive™


1. Soil and pH Needs

Ornamental Peppers like rich, loose and fertile soil which drains well. However, they do not perform well in wet, poorly drained soils. Heavy clay soils will retard root growth and starve the plant of oxygen, which can lead to root diseases. Soil should be amended with fully composted organic matter prior to planting and in the case of clay soils the addition of Canadian sphagnum peat moss and well-rotted compost are good sources of organic matter that will aid in aeration. If possible, incorporate two to three inches of organic matter into the top six inches of soil. If adding organic matter, be aware that organic matter that has not been fully composted will tie up nitrogen and sulfur leading to nutrient deficiencies and poor growth.  Soil pH should be 5.8 - 6.3 for optimum nutrient uptake; and should be tested prior to planting but after adding any amendments. This can be done quite easily with a portable pH tester. Mix one part soil with two parts distilled water, stir well and wait thirty minutes, then follow the instructions for using the pH meter. If pH is too low, the addition of lime is warranted. However, the rate will vary depending on how much you need to raise the pH and the type of soil you are dealing with. Clay soils or those with a lot of organic material have a high buffer capacity and require more lime than sandy soils, which have a low buffering capacity. A good soil testing lab can determine the lime requirement index (LRI) of your particular soil and can recommend types and rates of lime to use. The frequency of watering will depend on the type of soil, weather conditions and the amount of mulch. Mulch will not only reduce soil water evaporation but will also reduce splashing of water onto the lower leaves, moderate soil temperatures and reduce weed competition. Allow the soil to dry slightly between watering; if Ornamental Peppers are kept too wet it will lead to problems with root rot.


2. Fertility

Ornamental Peppers are moderate feeders in the landscape. Feed your peppers with a complete garden fertilizer, preferably one that is higher in phosphorous such as a 10-20-10. In areas of high irrigation and high temperatures it may be better to use a formulation with a slower release rate since higher temperatures will cause the fertilizer to be released quickly. Fertilizers that are not CRF are not recommended since the fertilizer will be leached out of the root zone long before the crop needs the nutrients. In high pH soils (alkaline soils) additional iron or iron sulfate may be beneficial to reduce chlorosis (yellowing) of the foliage.  Yellow foliage on Ornamental Peppers may also be caused by a nitrogen deficiency within the plant. Both can be corrected with the proper supplemental fertilizers. 


3. Disease

Water correctly to prevent most of the fungal diseases that can cause problems for Ornamental Peppers such as: botrytis and pythium.  Botrytis will develop as tan spots on the foliage. Established plants that are infected will rot at the crown, and the infected tissue will be covered with dusty gray fungal growth. Pythium rot will develop as shiny, blackened areas on the stems and petioles of established plants.  These areas often occur at or just above the soil line and plants will ultimately collapse and die. The best preventative is to use drip irrigation. At the very least, direct water from the hose onto the soil or mulch, and not on the plants themselves. Ornamental Peppers are also susceptible to Impatiens Necrotic Spot Virus (INSV). INSV appears as a dark, greasy stem lesion or a dark ringspot on the leaves. The disease is spread by western flower thrips, and once the plant is infected, it needs to be discarded. Western flower thrips control is required to control this disease.


Typical symptoms of botrytis


Pythium infected root system


Pepper plant showing signs of INSV


 4. Insects

You may find aphids, spider mites or thrips on Ornamental Peppers. Aphids are tiny soft bodied insects that cluster on the growing tips of leaves and flower stems, sucking plant juices. The plants become stunted and deformed. Thrips can feed on the upper surface of leaves leaving them silvery looking; they also like to feed on the pollen in the flowers which can distort their appearance. Spider mites feed on the underside of the leaves. This feeding causes yellow spots to form which results in decreased plant growth and production. A healthy, vigorous plant is less susceptible to pest damage than an unhealthy plant.  


Aphids on the leaf underside


Spider mite damage


Pepper plant showing thrips damage


5. Tips for Success

  • The worst enemy of Ornamental Peppers is having the roots standing in water.
  • Ornamental peppers prefer full sun in rich, well-drained soil and perform best in hot weather.
  • Ornamental peppers are not very forgiving of water stress, and repeated wilting can lead to lower leaf loss, fruit drop and a poor-quality crop.
  • Remove weeds from the plantings that compete with Ornamental Peppers for moisture, nutrients and light.

Information provided by Syngenta Flowers