Inspect the pepper's color. Select those that are deep green and glossy, with a hint of color change to an orange or red on a small part of the pepper.
Examine the shoulders of the pepper, where it curves toward the stem. Jalapeno peppers develop small cracks in the skin on the shoulders when they are ready to pick.
Hold the jalapeno in one hand and cut through the stem with a small knife or shears. Avoid pulling the pepper off the plant because this can damage the plant and prevent further jalapenos from developing.
Most mature jalapeno peppers grow to 2 to 3 inches in length, but mature peppers can be smaller or larger depending on the variety and the culture conditions in which it was grown.
Refrigerate jalapenos in the crisper drawer for up to one week.