Growing jalapenos from seed isn’t difficult and ensures plenty of peppers for your kitchen. Jalapeno pepper plants thrive in garden beds or containers and starting your own seeds allows you to choose from the many varieties available from seed catalogs. In this article you’ll learn all about growing jalapenos from seed in cell packs, pots, soil blocks, and paper towels, plus get expert tips for success. 

What are jalapenos?

Jalapeno peppers, like bell peppers, are a member of the nightshade family along with tomatoes and eggplants. The plants produce medium-sized fruits that are glossy green maturing to bright red. Most gardeners harvest green jalapenos, but red jalapenos contain more capsaicin, the compound which gives them their heat. Therefore a red jalapeno is hotter than a green fruit.

And speaking of heat, expect mildly hot jalapenos to fall somewhere between 2500 and 8000 on the Scoville scale. They’re my favorite hot pepper to grow and eat and I use them raw and cooked in a wide variety of dishes. If you have too many peppers to use fresh, jalapeños are delicious pickled or freeze them whole for winter cooking. 

Why you should be growing jalapenos from seed

Among the most popular types of hot peppers to grow, jalapeño seedlings are widely available at nurseries. So you may be wondering why should you consider growing jalapenos from seed? The biggest reason is variety selection. Nurseries have only a few options, but there are lots of excellent varieties available in seed catalogs that offer a range of improved characteristics like early maturity, large fruit size, compact growth, and higher yield. My go-to jalapeño varieties include Jedi, Jalafuego, and Pot-a-Peno.

Growing jalapenos from seed also means you can time planting so that your seedlings are at the ideal stage of growth when the conditions are right for transplanting outdoors. This gives them a strong start to the growing season. Plus, if you have a large garden and plant a lot of jalapeño peppers, sowing your own seeds can save money. 

4 Options for growing jalapeños from seed

There are various options for starting jalapeño seeds inside. You can sow them in cell packs and seedling trays, 4 inch diameter pots, soil cubes, or germinate them in paper towels and then transplant them into potting mix. Here is more information on each of these choices.

• Cell packs and seedling trays – Using cell pack inserts in seedling trays is a popular way to start a lot of seeds at once. Plus, the standard 1020 trays, which are 10 by 20 inches fit neatly under most types of grow lights. There are various types of cell packs, as well as plug trays, and most are inexpensive and reusable. 
• Pots – If I’m just planting a few jalapeño pepper seeds I’ll use 4 inch diameter plastic pots, sowing two seeds per pot, eventually thinning to the strongest seedling. I like plastic pots as they’re durable, reusable, and don’t dry out quickly or get moldy like fibre pots.
• Soil blocking – I started soil blocking around five years ago and it’s now my primary method for starting all types of seeds. Soil blocking uses metal blockers to form cubes of potting mix. There are various sized blockers available, but I find the 1 1/2 or 2 inch blockers to be the most useful for starting jalapeno seeds.
• Paper towels – Do you know how to start seeds in a paper towel? This method is ideal if your seeds are a couple of years old and you’re not sure if they’re still viable. The seeds are sprouted in damp paper towels and then transferred to cell packs or pots to grow on. So easy!

More on all of these techniques below.

When to plant jalapeño pepper seeds indoors

An important step to success in growing jalapenos from seed is knowing when to sow the seeds. Too early and you’ll end up with huge seedlings that outgrow their indoor space before it’s warm enough to be moved outside. Start them too late and you’ll be transplanting tiny, vulnerable seedlings outdoors that might not have enough time to mature their fruits before the end of the growing season.

I start jalapeno seeds inside 8 to 10 weeks before my last expected frost date. This planting time results in vigorous seedlings that are the perfect size when the time is right to transplant them into my garden.

Growing jalapenos from seed: 4 easy and effective options:

Option 1: Planting jalapeño seeds in cell packs and seedling trays

To sow pepper seeds in cell packs and trays, place the cell pack insert into the 1020 seeding tray. Fill the inserts with damp potting mix and place 1 to 2 seeds per cell, planting them a quarter inch deep. If using 2 seeds, you’ll need to thin to the strongest seedling once they’re growing well. Keep humidity high for good germination by covering the tray with a clear plastic dome or a sheet of plastic wrap. I remove the cover as soon as the seeds sprout for good air flow around the plants.

When planting hot pepper seeds in cell packs, I also use a seedling heat mat. This raises the soil temperature which boosts the germination rate and speeds up sprouting. Once half of the seeds have emerged, I turn off the mat.

Option 2: Planting jalapeno seeds in pots

Growing jalapeños from seed in pots is very similar to planting them in cell packs and trays. Be sure there are drainage holes in the bottom of the pot. I like standard square or round 4 inch diameter plastic pots. When you’re ready to plant, fill these with the moistened growing mix and plant 1 to 2 seeds per pot a quarter inch deep. As the seedlings sprout and grow, remove the weakest seedling by clipping it out at the soil surface. Pulling it can disturb the roots of the remaining seedling. 

I don’t use as seeding heat mat when planting in pots as the mats don’t generate enough heat to warm the larger volume of soil.

Option 3: Planting jalapeno seeds in soil blocks

Start jalapeno pepper seeds in 3/4 inch, 1 1/2 inch, or 2 inch diameter soil blocks. Using the soil blocker, form the square cubes from dampened growing mix and place them in a seeding tray. Plant one seed in each block, carefully covering it with a quarter inch of growing mix. Move the tray on top of a heating mat to boost germination. If I’m using the small 3/4 inch diameter soil cubes I will eventually transplant the seedlings into 2 inch soil cubes using square dibbles to make the perfect sized holes. 

Option 4: Planting jalapeno seeds in paper towels

The final method for growing jalapenos from seed is to start the seeds in moistened paper towels. Start by pre-soaking the seeds overnight in room temperature water. This helps soften the seed coat to break dormancy. Move the seeds to the bottom half of a sheet of paper towel. Fold the other half over the seeds and spritz with water to ensure the paper towel is evenly damp.

Move the folded paper towel into a plastic container or a zip top baggie, sealing it shut. Keep the baggie in a warm spot or place it on top of a seedling heat mat. Check daily to see if any of the seeds have sprouted. Once you spot baby roots emerging from the seeds, transfer them into soil blocks, cell packs, or pots, placing them a scant quarter inch deep.

More tips for growing jalapenos from seed

Once the pepper seeds have geminated and started to grow, you’ll need to follow a few steps to promote healthy pepper plants. Here are a few tasks to keep in mind.

• Good air circulation – As soon as the seeds sprout, remove any plastic domes or plastic wrap to encourage good air flow. This helps prevent damping off, a common issue when growing seeds indoors. Adding a small oscillating fan to your seed starting space is an easy way to keep air moving. 
• Watering – The fastest way to kill your baby pepper plants is overwatering. The goal is to maintain a lightly damp – not wet – growing mix. Don’t water on a schedule, but instead water when the soil is dry to the touch. As the seedlings grow you’ll need to water more often. 
• Fertilizing – Start to feed the seedlings with a liquid organic fertilizer when they have developed two sets of true leaves. Because the tiny plants don’t need a full feed, dilute the fertilizer product to one-quarter strength, applying it to the soil every 10 to 14 days. 
• Hardening off – Hardening off seedlings is an essential step in acclimatizing your jalapeño plants to outdoor growing conditions. Start the process in late spring about a week before you wish to transplant them in your garden. Read this hardening off guide to get expert tips on the process.
  

Transplanting jalapeno pepper seedlings

If you can, transplant jalapeño pepper seedlings into a sheltered location in your garden or in containers on an overcast or drizzly day. This reduces plant stress. They grow best and produce the most peppers when exposed to 8 to 10 hours of sunlight daily. I also work in compost or rotted manure before planting and an organic vegetable fertilizer. The nitrogen in the fertilizer supports leafy growth, while the phosphorus and potassium encourage root growth and blossoms as well as fruit production. 

Space jalapeno plants 12 to 18 inches apart and insert a stake or tomato cage to offer support as they grow. The stems and branches of peppers can be brittle and prone to breaking in high winds. Supporting the plants reduces damage. If there are cold night temperatures in the forecast, cover the plants with a mini hoop tunnel or row cover. Remove the cover during the day so they can enjoy the warmth of the sun.

I find jalapeno peppers easy to grow and not prone to common problems like pests and diseases. However, it’s a good idea to keep an eye out for culprits like aphids, spraying with a jet of water or insecticidal soaps when necessary. Reduce pest issues by attracting beneficial insects, like ladybugs, to your garden by planting companion plants for peppers.

For more advice on growing peppers, be sure to read these excellent articles:

• How to plant and grow cayenne peppers
• Pruning pepper plants: A how-to guide
• Growing shishito peppers in gardens and pots
• Watering peppers: Expert tips