Peppers don't like it too wet, so make sure you're not over watering. You can use a water meter, but I like to go by weight.

Double the dosage and apply again

Keep fertilizing with dilute FP solution (perhaps half strength) at every watering for a couple weeks. At some point, you'll need to switch to a lower nitrogen fertilizer for fruit production, however. Make sure the water is penetrating into the mix, and not just running straight through (use your finger and/or wooden dowel).

Other than that, give it time! Plants need some time to get established.

Erm I didn't know that we needed to switch off of FP when we wanted fruiting?

I have quite a few bell (and hot) peppers that I'm growing in small pots this year. So far I've just been giving them 1 tsp per gallon once a week with Osmocote Plus timed release in the pots as well.

Could you please elaborate on the fertilizer switch? When to switch, what to switch to, and the reasoning behind it? Or point me to a post discussing it? Thanks.

Thanks everyone for the responses. Definitely not too wet. They looked greener yesterday, so they appear to be doing better. I'm going to keep experimenting with a little extra FP. My mix drains very well, maybe too well, and I need to make sure the top 10" or so stays moist. I planted the last pepper plant in the ground. It still looks much better than the container peppers.

I've been growing peppers in containers for many years and generally found that they don't seem to need as much fertilizer as other members of the nightshade family (tomatoes, eggplants, potatoes). I do use about 1 tablespoon each of Tomatotone and Osmocote Pro (with all the micronutrients) per gallon of potting soil because we often have four to six weeks of heavy rain in the beginning of the season, and I want to make sure to start them off right. This works out to a N-P-K formula similar to using Foliage Pro.

Once the plants are fruiting heavily, I plan to start feeding them lightly with each watering. I plan to use the Foliage Pro then, while also adding Protek, which is similar to reducing the amount of Nitrogen. Al discussed the issue of reducing the amount of Nitrogen to induce fruiting in the thread linked below.

I should add that I have been a pretty successful container gardener for many years, but this is my first year using Al's 5-1-1 mix in my containers along with Foliage Pro. I'm already seeing excellent results, but we're only a couple weeks into the season.

Here is a link that might be useful: When should I induce N deficiency

That's almost exactly what I've done. I used MG shake and feed with micro's as a crf, and I use FP w/Protek. We've had warm windy weather lately and my containers are drying up fast. I might actually have not enough water retention, so I am watering more often. Peppers still aren't keeping up, but this year is a total learning experience with containers and 511 mix.

We have a lot in common. I just realized that you are the only one who responded to my question about growing watermelons in containers. We're both in USDA zone 5, where the weather has been unusual this year. This is my first year using 5-1-1, and I have great hopes for it. But, I have found that there is a bit of a steep learning curve, especially whEn it comes to watering. My peppers were the last things I planted, and they're in 20 gallon pots. The weather's been very hot the past week, and I've had to water them copiously every other day. I'm hoping this is just a matter of getting the 5-1-1 mix fully saturated, and the young roots established. I don't have any fear of overwatering with this mix, even if it should turn cold and wet.

Please keep us informed of your experience, even if it is disappointing. I promise to do the same. This is how we all learn.

Thanks for the information and the link.