Sweet or hot, bell-shaped or elongate, all peppers are members of the nightshade family.
People have been growing peppers for several thousand years. Native to the Americas, peppers (Capsicum) are now grown all around the world. Spicy peppers are commonly called chilis and sweet peppers are called bells. In Singapore, India, and Down Under, the bells are called capsicum. The popular spice, paprika, is made from a type of capsicum fruit.
Peppers are usually classified as sweet (bell) or hot (chili). All peppers start out green [think green beans]. If left on the vine long enough, different varieties may turn yellow, red, orange, or purple. Depending upon who you ask, there are 20 to 27 species (and hundreds of varieties) of peppers. These five species of Capsicum are domesticated:
All peppers are self-pollinating, but crops are significantly larger when other pepper plants are nearby.
Hot peppers and the Scoville scale
Hot peppers are rated using the Scoville scale. Scoville heat units (SHU) are a function of the amount of capsaicin found in the fruit. For comparison, pepper spray used by law enforcement can have 500,000 to 1 million SHUs and sweet bell peppers have a Scoville rating of zero. Here are some common peppers and their Scoville ratings:
Choose your pepper accordingly (and be sure to wash your hands after handling hot peppers and their seeds before you do ANYTHING else). Seriously.
How to grow peppers
Peppers love warm weather. In fact, there’s no sense starting pepper seeds early, because they won’t germinate. Even if they do, they won’t grow well. To get a head start on the growing season, many gardeners use seed heating mats. The soil needs to be 70 to 84 °F for peppers to really get going. Peppers prefer loose, loamy soil (or even sand), so you may want to grow them in raised beds or containers. Peppers can also grow well in straw bales. Seeds should be planted 1/4 inch deep. Ultimately, you will want to place plants 18 to 24 inches apart. When thinning, snip unwanted plants off at soil level to avoid disturbing other plants’ roots. At first, the soil should be kept moist but not soggy. Soggy soil can cause damping-off disease.
Pepper pests and diseases
Like many other of our favorite food plants, peppers are in big demand in the insect world. Cutworms, aphids, armyworms, flea beetles, leafminers, corn earworm, leafrollers, nematodes, weevils, thrips, spider mites, tomato psyllids, and whiteflies should be watched for, and some birds may want to take a bite, as well. Most pepper diseases are of the fungal variety: powdery mildew, crown rot, root rot, verticillium wilt, and tomato spotted wilt are common on Bay Area peppers. Also bacterial spot, several mosaic viruses, blossom end rot, and curly top may occur. Sunburn, or sun scald, can also be a problem on pepper plants. While too much nitrogen can cause excessive vegetative growth and not much fruit, the opposite is also true: low nitrogen levels can reduce leaf coverage to the point that fruit is damaged. Row covers can also be used to reduce sun exposure, once fruit set has occurred.
One of the most common mistakes gardeners make when harvesting peppers is that they do it too soon. If your peppers feel thin-skinned, give them some more time.
We’ve all heard some seeds or plants described as heirlooms and others hybrids, but what do those terms really mean?
Both hybrids and heirlooms come about through naturally occurring cross-pollination, as opposed to genetically modified organisms (GMOs), which are created in a lab using altered DNA strands. Personally, I think we are setting ourselves up for a Major Fail, messing with DNA that way. I do not use GMO seeds or plants in my garden or landscape.
[Did you know that some governments (the USA included) have passed laws making it illegal to save or share certain seeds harvested from plants grown at home? This is because some GMO and hybrid seeds have been patented by corporations.]
Before agriculture became an industry, people grow a wider variety of plants for food. That biodiversity helped offset inclement weather, diseases and pests, and other threats to a failed crop and the resulting starvation. Corporate agriculture, on the other hand, feeds countless millions by generating a smaller variety of uniform plants that consistently grow at specific rates, that can be sprayed with a variety of pesticides, herbicides, and fungicides, ship well, and store well. As many of you know, taste and texture often suffer s a result.
Pros & cons of heirlooms
Heirloom seeds are those that have been handed down, person to person, in a specific geographical region, for a very long time. Also, heirlooms are open-pollinated, which means pollination occurs naturally, by wind, birds, animals, and insects, and not by human efforts. Heirloom varieties are at least 50 years old (some say 100 years), and many of them have been grown consistently, in the same locale, since before WWII. These plants have evolved to take advantage of local microclimates and beneficial insects. Heirloom seeds are hand selected by gardeners from the very best plants each growing season. Many heirloom plants do not have the uniformity or long term storage capabilities of hybrids, but growers (myself included) claim that the flavor is significantly better. Heirloom crops have more variety in size and shape than hybrids, but they always grow true to their parent plants. Heirlooms are more genetically diverse, making them more durable as a species, and less susceptible to local pests and diseases. Heirloom offspring are fertile and can reproduce.
Pros & cons of hybrids
Hybrid plants are intentionally created by cross-pollinating different varieties of a species. The intention of hybridization is to take advantage of the best characteristics of each parent plant, creating what is known as hybrid vigor (heterosis). This vigor only lasts for one generation. Hybrid seeds do not grow true to their parents and they lack vigor and genetic diversity. This lack of diversity is what caused the Irish Potato Famine of the 1840s. If all the plants are identical, they are equally susceptible to pests and diseases. A single threat can be devastating.
Creating a hybrid that grows “true” to the desired characteristics takes years of diligent effort. Plants are often pollinated by hand or grown in greenhouses or pollination bags that block contamination from outside pollen to ensure that pollination only occurs between the desired plants. The majority of the fruits and vegetables you see in grocery stores are hybrids. Harvests are very consistent in size and shape. Hybridization is done for many specific characteristics:
When shopping for plants and seeds, one way to know if it is a hybrid is to look at the Latin name. If you see the letter “x” between words in the name, it is a hybrid. For example:
Raspberry (Rubus idaeus) crossed with blackberry (Rubus ursinus)
creates Loganberry (Rubus x loganobaccus)
*Check labels for the letters V, F, N, T or A. These symbols indicate a resistant to verticillium wilt, fusarium wilt, nematodes, tobacco mosaic virus or alternaria stem canker, respectively.
Understanding the difference between heirlooms and hybrids can help you make the right choice if you want to collect viable seeds from your harvest for next year’s planting.
PEST ALERT: Japanese beetles have found their way to California!
If you ever lived on the East Coast, you’ve probably seen the devastation caused by Japanese beetles. These shiny green and bronze pests skeletonize leaves and can completely defoliate smaller trees and shrubs. If that weren’t bad enough, their larva attack from underground, feeding on root crops and lawn roots.
Japanese beetle identification
Adult Japanese beetles (Popillia japonica Newman) are just under ½” long and slightly less wide. Males tend to be a little smaller than the females. Japanese beetles are easily recognized by their metallic green body and shiny bronze outer wings. They are clumsy flyers. Up close, five small tufts of white hair can be seen on either side of the body. Beetle larva are about 1” long and white, with a small copper-colored head and a larger copper-colored rear end. Like many other grubs, they rest curled up in a C-shape.
Japanese beetle lifecycle
Japanese beetles go through complete metamorphosis. Female beetles burrow into the top 2-4” of soil, normally in turf and lawns, to lay 40-60 eggs throughout an area. These eggs hatch as larva in midsummer. Larval beetles go through 5 molts (or instars), feeding heavily on turf roots and root crops for several months. In the final instar, they reach a pupal stage. The pupae are reddish-brown to tan and ½” wide. The larva often burrow deeper into the soil for winter. Damage to lawns is often the first sign of an infestation. Mature beetles emerge in late spring and early summer to begin feeding above ground and to look for mates.
Destructiveness of Japanese beetles
Adult Japanese beetles attack over 200 garden plants. Every part of the leaf is eaten except the veins, causing skeletonization. Favorite foods include tomatoes, grapes, peppers, roses, cherries, peaches, pears, raspberries, corn, blueberries, beans, and strawberries. For a complete list of host plants, see the Wikipedia page on Japanese beetles. Larval forms of the beetle feed for several months on lawn roots and some root crops. The first sign of Japanese beetle infestation may be dead areas of a lawn. A drench test can be conducted to see if grubs are the cause of the problem.
To perform a drench test, mark off a one square yard area of lawn (3’ x 3’) that includes both healthy and unhealthy grass with a rope or other clear marker. Mix 2-4 tablespoons of liquid dish soap with one gallon of water in a watering can. If the soil is especially dry, two gallons may be needed. Apply the solution evenly within the area. The soapy water will bring insects to the surface. Over the next ten minutes, check the area for visible signs of grubs and other insects.
How to control Japanese beetles
Pheromone traps are not recommended as a control for Japanese beetles. Research has shown that pheromone traps actually attract 25% more beetles than are captured. The majority of attracted beetles end up feeding on plants near the trap, rather than entering it. Beetles can smell the pheromone attractant from 1 kilometer (0.62 miles) away, so this method is counterproductive in areas with heavy populations. It may be effective locally, as we try to nip this potential tidal wave in the bud. Traps should be checked weekly.
Habitats can be modified by adding plants that are resistant or unattractive to Japanese beetles. According to Held (2004), in “Relative Susceptibility of Woody Landscape Plants to Japanese Beetle,” Journal of Arboriculture 30(6), pp. 328-335, dogwood, forsythia and hydrangea are just a few plants that Japanese beetles find distasteful. For a more complete list, see the North Dakota State University page on Japanese beetles.
Biological control can be achieved by introducing nematodes. Specifically, Heterorhabditis bacteriophora and Steinernema glaseri species have been effective. These nematodes are available commercially. They attack the grubs and should be applied in August.
Milky spore disease is also effective against Japanese beetles. This bacteria (Paenibacillus popilliae) is eaten by the grubs and then causes fat depletion, resulting in dead grubs. Milky spore is not available for sale in some states, but it can be used in California.
Insecticides have been used to control Japanese beetles, but timing is critical and the results may be a mixed bag. Systemic insecticides take time to work and must be applied repeatedly.
Japanese beetles were first found in the U.S. in 1916. Since that time, they spread west to the Rocky Mountains. Unfortunately, in 2015, a male and female Japanese beetle were found in Sunnyvale, CA. It was hoped that that was the extent of the infestation, but we won’t know for sure util a few months or even years have passed. If you think you see one of these destructive pests, please the call the Pest Hotline at 1-800-491-1899.
I hope this information inspires you to grow more of your own food. You can ask your garden questions on my Home page.