There are hundreds of varieties of sweet, mild, and hot peppers to grow in your garden and a pepper for every culinary use.
After tomatoes, the pepper is the most popular vegetable grown in most gardens (although it’s technically a fruit). Every gardener seems to have a favorite, whether it’s mild, hot, incredibly hot, sweet, yellow, red, purple, brown, or just a traditional green bell.
But given the same growing conditions, peppers can be much fussier than tomatoes. Even though the two are frequently grown together, slight changes in your local weather or rainfall can have significant impact on your pepper plants – anything from slowing their growth to killing them – while your tomatoes may continue to thrive.
Peppers are native to Mexico, Central America and South America, which will give you a clue in creating conditions favorable to growth. Plants native to that part of the world thrive on lots of sunlight, very warm temperatures and dry air. Not much has changed from the pepper plant’s perspective in spite of hundreds of years of breeding and cross breeding by humans.
From Wikipedia: “The misleading name “pepper” (pimiento in Spanish) was given by Christopher Columbus upon bringing the plant back to Europe. At that time peppercorns, the fruit of Piper nigrum, an unrelated plant originating from India, were a highly prized condiment; the name “pepper” was at that time applied in Europe to all known spices with a hot and pungent taste and so naturally extended to the newly discovered Capsicum genus. The most commonly used alternative name of the plant family, “chili“, is of Central American origin. Bell peppers are botanically fruits, but are generally considered in culinary contexts to be vegetables.”
Start peppers from seed indoors
Pepper plants bought at a nursery will sometimes mysteriously wither and die a few weeks after you transplant them to your garden. Assuming they are disease free, the culprit could be the change in weather conditions, light exposure, soil pH, moisture, or nutrient levels (fertilization). The best way to insure success for your pepper plants is to start peppers from seed indoors about 8 weeks before the last frost in your area. Many seed packages will recommend a start date 4-6 weeks before last frost, but I’ve found the extra weeks indoors makes the plants more hardy and able to withstand most of what your local outdoor conditions may throw at them.
Keep the soil in the starter pots as warm as possible (between 80-85 degrees) to insure quick seed germination. Peppers do best when they get off to a quick start.
Transplanting peppers to your garden bed
One week before planting, it’s essential that you harden off pepper seedlings. Transplanting them directly to your garden from under your grow lights, window sill, or the plant nursery can be lethal. They’ve been indoors in very controlled, consistently warm, windless conditions and now they’re subject to swings in temperature, wind, moisture, and new soil.
To harden off peppers, leave them on your porch or other sheltered outdoor space for at least one week, avoiding direct sunlight until two or three days before transplanting. Don’t feed the plants during this time and reduce the amount of water they’ve been used to. Keep the soil moist, but not saturated.
Wait to plant peppers until nighttime temps are consistently over 60 degrees (15.5 celsius) – usually 2-3 weeks after your last frost date. Plant peppers in a location that gets full sun all day. If that’s impossible, pick a location that gets sun in the morning until at least mid afternoon (some late afternoon shade can actually be beneficial).
Create a hole at least twice as large as the root ball and load the area around the roots with compost. Set the plant a little deeper in the hole than it was in the pot. Backfill with soil. Remove any flower buds at this time, as the immature plant won’t be able to hold the peppers. This will also encourage the plant to send out deeper roots and produce more flowers, which means a bigger, healthier plant with lots of peppers.
Space pepper plants at least twelve inches apart (depending on its mature size) and mulch to stabilize the soil temperature around the roots. Add additional compost around each plant’s root zone (but not touching the stem) every four weeks. Little else in the way of nutreints is needed, but if necessary, give them a feeding once a month of liquid fish emulsion to give them a boost – but be careful here, because this is a nitrogen heavy liquid fertilizer and too much nitrogen will create spindly, leafy growth and a plant unable to support the fruit.
After planting, pinch off the first flowers (I now it’s difficult, but it should be done). This encourages deeper root growth, earlier fruit production, and a healthier plant.
Peppers are sensitive to cool temps
Peppers need warm soil and air temperatures to thrive and you’ll notice almost immediately if they’re unhappy in the garden. Plants which seem to stop growing or begin to wilt are many times responding to air and soil temps which are too cool. Peppers grow best when daytime temps are in the 80-85 degree range and nightime temps are around the 70 degree mark. Frost is an absolute killer for them. If you experience a cool early season, cover the peppers with milk jugs to keep them warm until temperatures rise. Floating row covers are a good option, too. The warmer you keep the plant at night, the more growth you’ll see.
If you live in Northern latitudes with late-to-rise soil temps, try covering your garden bed with black garden mulch for one week prior to transplanting. The black plastic will seal in the heat and warm the soil about ten degrees. If you want to leave it in place, cut a hole in the plastic before planting each pepper.
Peppers don’t need loads of water, so give them one deep watering (one inch of water) each week and they’ll be fine. Too much water increases the chance of fungal infection and too little water may result in bitter fruit. Water the roots, not the foliage – this is really important as many fungal diseases of peppers and tomatoes are encouraged by wet foliage. Mulching the root zone helps retain moisture in dry weather.
Diseases of peppers
Most diseases of peppers are bacterial or fungal, usually caused by too much moisture and consistently wet foliage and fruit. It can also be caused by the previous year’s infected crop, as bacteria and fungi frequently overwinter in the soil. Crop rotation reduces the chance for infection, but don’t follow tomatoes with peppers as they are vulnerable to many of the same diseases.
If you have consistent problems with these diseases, grow resistant varieties (symbols indicating resistance are on plant tags and seed catalogs).
The most common pepper diseases (click links for images)
Anthracnose infection appears on fruit as soft, dark watery spots
Bacterial spot appears as yellowish, green raised spots on young leaves. Dark spots with light-colored centers appear on older leaves and fruit
Early blight appears as dark spots on leaves, stems, and/or fruit, eventually killing the plant
Verticillium wilt appears as discoloration on lower leaves first and moves up through the plant
Mosaic Virus appears as dark and light splotches on the leaves of young plants. Later, they curl and wrinkle and fruit becomes bitter.
If you spot any of these diseases, remove all infected leaves, stems and fruit immediately and dispose – do not compost.
All peppers first appear on the plant as green peppers. As they mature they take on the characteristics of the mature fruit: sweet, hot, mild, red, yellow, orange, brown, purple, etc. They can be eaten anytime after they appear to be full size, but the sugars and heat don’t enter the fruit significantly until they take on the mature size and color, at least 8 weeks after transplanting. It’s actually a good idea to harvest some of the peppers early, as it will signal the plant to produce more fruit.
I’ve learned the hard way that one should use a heavy duty scissors or knife to cut the peppers from the plant, instead of trying to snap them off. When I’m impatient or lazy about this, I’ve ended up with half the plant in my hand and immature peppers lost. The plants are remarkably easy to break, considering the weight of the fruit.
If you’re saving pepper seeds, save the seed from the first pepper that grows to perfection. This is the seed best adapted to your climate and soil. Saving pepper seeds is incredibly easy. Just take out the core of the pepper, separate the seeds and let them dry on a paper towel for a few days. Then mark a plain white envelope with the type of pepper you took the seeds from and the date and year you harvested it. Place the seeds in the envelope and put the envelope into an airtight plastic jar (like a caning jar). Store in the refrigerator until next spring. Pepper seeds remain viable up to three years.
Green, immature peppers can be set next to apples to ripen indoors. Because peppers are fruit, the ethylene gas that ripe apples give off triggers the peppers to set color and sugar.
Peppers like the company of carrots, tomatoes and onions, and herbs like parsley and basil.