Growing Guide: Jalapeño Peppers

Plant: Jalapeño Peppers

Genus: Capsicum

Family: Solanaceae

Hardiness Zones: 11 (USDA); grown as an annual everywhere.

Sun: Full sun (6-8 hours)

Flavor Notes: 2,500 to 8,000 Scoville heat units. Jalapeños are typically picked while they are still green in color and not totally ripe. In their green form, jalapeños tend to have a bright, grassy flavor. They can even have a slight bitterness to their taste. A totally ripened red jalapeño pepper will lose the bright, bitter flavor and gain in sweetness (and often overall median heat). The heat comes from the capsaicin found in the pepper, so the red version – with more time on the vine – tends to be hotter than green.

Origin: Mexico

General Growing Information:

Healthy jalapeño peppers require plenty of room to grow, flourish and thrive, along with a considerable amount of light.
They grow best when planted in soils with good drainage and average fertility.
They should be planted outdoors during the spring when the soil temperature reaches about 65 degrees Fahrenheit; the peppers are sensitive to cooler temperatures at night.
When you plant jalapeños in the garden, leave enough space for the peppers to grow. Or, if you're using a container, plant one jalapeño pepper plant per 5-gallon pot.
Before planting jalapeño seedlings in the garden, take them outside to harden off under dappled shade for approximately 10 days.
Space them approximately 2 feet apart to allow room for growth. You can use stakes to support the top weight if needed.
Mulch around the base of the plants, keep the soil moist but not over-saturated.
Fertilize about every 4 to 6 weeks.
The jalapeño pepper plant is relatively hardy, but it can be vulnerable to certain pests, including aphids, mealy bugs, scale and whitefly. Identifying and treating the infestation as early as possible with the least toxic option is the best bet in growing and maintaining healthy jalapeño peppers.
Peppers are light feeders, but will benefit from a regular feeding of a well-balanced, organic fertilizer or compost tea. Avoid high nitrogen fertilizers. They create lush foliage, but poor peppers.

Starting from Seed

To start growing jalapeño from seed, sow the seed at least 10 weeks before setting them into the garden in early to mid-March. Seeds should germinate in about 10 days, and they do best in temperatures of around 80 degrees. If you're growing jalapeño peppers indoors, place the seedling trays on a heated pad.
Keep the soil consistently moist, but never too wet while the seeds propagate. Keep out of direct sunlight until the first sprouts appear.
Germination should occur within 7-21 days but sprouting can take up to 40 days, so be patient and don't give up on them.
Before you plant them in your garden, your jalapeño pepper plants should fill the container with white roots and be about 6 to 8 inches tall.
Once they sprout, it is recommended to give them a gentle breeze from a fan to strengthen their stems, and/or gently brush the seedlings daily with your hands. This will prevent dampening off, a common ailment that causes seedlings to shrivel up and die. This helps strengthen their stems as well and grow stockier instead of thin and leggy.
Be sure to keep the light source as close as possible to the seedlings and move it up as they grow taller.
Keep your grow light on for 12-16 hours a day.
Pinch off any blooms before transplanting so the plants put more energy into growing.

Specific to Colorado Growing:

When growing peppers in Colorado, start the seeds indoors in February/March to get the going earlier than other veggies, as the seeds often take longer to germinate than tomatoes and other veggies. It's good to keep the seeds quite warm to germinate (80-90˚ F), and keep to them indoors until it gets to be about 60˚ outside even at night (usually this happens in late May to early June).

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