To grow a serrano pepper plant, place seeds 1/4-inch deep in well-drained, warm soil in a location that receives plenty of sun. This tender plant should be started indoors in planters, unless the outdoor temperature in your area is warm, and there is no chance of frost on the ground in the morning. You need serrano pepper seeds, a large planter garden and loam soil, a mix of soil and sand, and you may need a heat mat to maintain warmth of the soil.
- Prepare the soil
Pour loam soil into a large planter to within a few inches of the rim. Place the planter in the sun to allow the soil to warm to between 80 and 85 degrees Fahrenheit. You may also use a heat mat placed underneath the planter to maintain the temperature.
- Add the seeds
Place several seeds into the soil about 1/4-inch deep. The seeds should be placed at least 12 inches apart.
- Give the seeds water and sunlight
Add enough water so that the soil is fully damp all the way through, but not soaking wet. Place in direct sunlight, rotating the plant every few days. Water whenever the soil starts to feel dry. Once the serrano pepper plant starts to grow significantly, you may need to insert wooden stakes to keep the plants upright.