So About Those Peppers

Said I’d talk about peppers. Here we are.

Peppers are interesting in Kansas City because our summer is almost perfect for them, but our spring is not. They need warm soil and warm nights to do anything, and we have about six weeks every year where the days tease you into thinking it’s time, but the overnight lows haven’t caught up. The result is a lot of people transplanting peppers in late April, watching them sit motionless for a month, and assuming something is wrong. Nothing is wrong. The plant is just cold.

Soil temperature is the number that matters. Peppers want 65°F minimum at root depth before they do much of anything. At 60°F they survive. Below that they stall, sometimes permanently. We crossed that threshold reliably about ten days ago in KC. Mid-May transplants will catch up to plants that went in three weeks earlier in most years, and they’ll do it faster because they’re going into warm soil instead of cold.

See the full Vegetable Guide for pepper variety details and spacing.

What to Plant

For sweet peppers, California Wonder is the standard for a reason but it’s not the most interesting option. Banana peppers are incredibly productive in our heat. Shishito peppers are worth growing if you’ve never had them roasted. Carmen is a sweet Italian frying pepper that produces heavily and handles our August heat better than most.

For hot peppers, KC summers are legitimately good. Jalapeños are reliable and prolific. Cayenne does great. If you want to go further up the heat scale, habaneros and Hungarian wax both perform well here. The heat actually improves the closer we get to August, so don’t harvest everything early.

One note on hot pepper varieties: the plants get big. A mature habanero can reach three feet wide. Give them the space.

The Stall Is Normal

Transplant a pepper in May and it will sit there for three to four weeks doing what looks like nothing. This is normal. The plant is establishing roots, not putting on top growth. Resist the urge to fertilize heavily to push it. Too much nitrogen early on produces big leafy plants that set almost no fruit. Go light on nitrogen and let the plant develop at its own pace. Once it starts flowering, back off nitrogen entirely. Phosphorus and potassium from this point on.

The first flush of flowers often drops without setting fruit. This is also normal, especially if nights are still cool or if there’s been a lot of rain. The second flush typically sets. Don’t pull the plant because the first flowers fell.

Water and Heat

Peppers handle our summer heat well but they need consistent moisture. Irregular watering — especially the wet-dry-wet cycle you get from relying only on rain — causes blossom end rot and cracked fruit. Mulch heavily around the base of the plant to retain soil moisture and moderate temperature. Two inches of straw or wood chips makes a real difference in July and August.

One thing that catches people off guard: peppers can drop flowers when temps consistently hit 95°F or above. We get stretches of that in late July. The plants don’t die, they just pause. When the heat backs off into the upper 80s, flowering resumes. It’s frustrating to watch but there’s not much you can do about it besides keep the soil evenly moist and wait.

Harvest Timing

Almost every pepper variety can be eaten at the green stage or left to ripen to its final color — which is usually red, orange, or yellow depending on the variety. Fully ripe peppers are sweeter and have more vitamin content. They also take another three to four weeks after the green stage to get there. Leaving fruit on the plant to ripen slows production of new fruit. The tradeoff is yours to make.

If you want maximum production, pick peppers at the green stage and keep picking. If you want maximum flavor, let a few ripen fully and accept that the plant slows down while they do.

We’ve got about four solid months of pepper weather ahead. Get them in this week if you haven’t already.