Vegetable Gardens

» Sally Morton - growing yellow and red peppers

I apologize for the delay in answering - I have been away. Your maturity will depend on what day in June and whether you started with seed or transplant. Below, I will give some facts to help you calculate.
Generally, it takes 100 to 120 days for peppers to mature from seed; 70 to 85 days to mature from transplants. (Check the seed packet of the specific type of pepper you planted. Or stick the name of the pepper plant variety into Google's search engine and it will bring you up days to maturity for that specific variety.)
Let's assume you planted from seeds on June 1st. From June 1st to July 1st is about 30 days (we're going to round off) and from July 1st to August 1st gets you to 60 days. August 1st – August 18th , add another 17 days. That is a total of 77 days. You still have a way to go to get to 100 or 120 days from seed. If you started from transplants, you would be looking at ripe yellow or red peppers any day now!
Specifically for the Colorado region, with your short growing season, you can use "season extender" tips to help you extend your growing season and get mature peppers quicker.

See this page from University of Colorado Extension: Extension webpage.

1st season extender tip: Start seeds in greenhouse 40 to 50 days prior to the last frost. Transplant 6-week old plants after the ground warms up in spring.

2nd garden tip: Colloidal rock phosphate as soil amendment, along with kelp (seaweed) increases yield.

3rd tip for short season: If you have a short season and you want red fruit, allow the earliest fruit to remain on the plant while harvesting subsequent fruit. That will keep the plant producing. (If you don't want green, give away any you harvest!)

4th Garden Tip: If your peppers ever turn red, check out these recipes from a Colorado greenhouse. Their website.

The passages below are taken verbatim from the above given extension guide for peppers in Colorado:

"Peppers may be classified as sweet or hot, or by color. Most peppers either are green or yellow when immature. When they reach their maximum size, they usually turn red, similar to a tomato (to which they are related). Because the Colorado growing season is short, peppers generally are harvested before they turn red, although small peppers generally produce a fair percentage of red fruit. All peppers, including ornamental peppers, are edible. However, be careful tasting peppers of unknown hotness.

The following pepper types and varieties have done well along the Front Range.

• Bells: Predi (large, elongated), Figaro (blocky), Jingle Bells (little), Islander (purple)
• Bells, tapered: Ori (green), Fry King (yellow)
• Cayenne: Super Cayenne
• Cherry: Sweet Cherry, Hot Cherry
• Chili: Super Chili (red), Hot Portugal (green), Paper Dragon (yellow)
• Jalapeno: Jalapa
• Ornamental: Candle Light

Harvesting

"It's best to harvest with hand pruners to avoid damaging the plant. You can enhance production by harvesting often. When fruit reaches acceptable size, remove it from the plant. If maximum-size fruit is desired, remove all but one or two fruits so they will receive all the plant's resources.

"Flavor or pungency is not influenced by maturity, so fruit may be harvested at any stage of maturity. If red peppers are desired, allow the earliest fruit to remain on the plant while harvesting subsequent fruit."

This is also a great "how to" page on peppers from Mother Earth News for your reference.