For containers, you should use a soil-less medium, and most of them are peat based. The only potting medium I use, at present, uses conifer bark as the main ingredient along with peat moss, and perlite. Commercial potting mediums will be pH adjusted, and will contain either calcium or gypsum. I have, in the past, mixed a very large percentage of bark fines into a regular potting mix, and have been happy with the results. Whatever you do, don't put a shovel full of your best outdoor soil into your containers. Even the finest garden soil turns into something awful when removed from a soil SYSTEM and made to live within the confines of a container.

You potting mix find looks OK, to me. But why are you getting into action so late in the season? Peppers ,from seeds, need a good 6 weeks time to develop into what is suited for plant out, either in a pot or in the garden. I notice you are in zone 5 but still it is a bit too late(to me). So if you start them today, they will be ready like 15th of June for plant out. And that is if your indoor growing condition is flawless. If I were you , I would look into plants. You might not be able to find Reaper but ther are all kind of Habaneros, Jalapenos, ... I suggest you visit "Hot Peppers" forum. There are quite few experienced and knowledgeable pepper growers.

I've made a mix similar to Al's 5-1-1 mix many times, using whatever I could find that was close to or similar to pine bark fines even if it wasn't labeled pine bark fines. I've used pine bark mulch that had pieces too large to be considered fines, but only a little too large and I just removed any chunks I thought were too big and threw them on top pf a shrub bed as mulch . They worked just fine. I've also used a bagged product from Home Depot that is labeled "soil conditioner". It contains both pine bark fines and humus, but most bags have a lot more pine bark fines than humus. The brand they carry varies from year to year and some years the pine bark is bigger than I'd like, but I've used it anyway and it worked fine. In our climate's hot weather, the bark breaks down fairly quickly anyway. Be very careful if you purchase a compost product, whether it is manure-based or not. We have had issues since the early 2000s, both in the USA and the UK, with a certain class of persistent herbicides that persist in manure and compost, as well as in grass clippings, straw and hay. Once these herbicide residues make their way into your soil or soil-less mix, they can damage and kill your plants for years. You can do a search on "killer compost" or "contaminated compost" on Google to read about the issue or you can do a search here on this forum to read previous posts about it. It is a very critical issue for gardeners that does not get much attention in gardening publications. Both Organic Gardening magazine and Mother Earth News do mention the issue of contaminated manure and compost pretty regularly. I have gotten to where I won't hardly purchase manure or composted manure any more because of this issue, and I regularly turn down free cow or horse manure offered to me by our ranching neighbors because they often use purchased hay and there is no way to be sure that these herbicides were not sprayed on the hayfields since one of their primary uses is to keep broad-leaved weeds out of hay pastures. The two kinds of purchased, bagged manure or compost products I still trust enough to use are: 1) mushroom compost (mainly because I've never gotten a bag of it that is contaminated), and 2) Black Kow cow manure (for the same reason). The other reason I use Black Kow is because it is 100% manure and my experience with many other bagged manures is that they often have a lot of filler material and contain very littler manure. By law they only have to contain 10% manure, and most other bagged cow manure products are not 100% manure. Often the filler is black clay which I do not want to add to my soil-less mixes or to my garden soil since our soil already has a very high clay content. I am even careful about using chicken manure from our own chickens nowadays and compost it separately from our regular compost pile. Why? Because some commercial compost sold in bags a couple of years ago contained herbicide residues that killed garden plants. When they attempted to figure out how the compost became contaminated, it was found the contamination came from animal manure from animals that had been fed bagged animal feed. Apparently some component of that name-brand animal feed had been raised using one of those persistent herbicides and the herbicide residue survived both the digestive tract of the animals and the composting process itself. I don't normally use that brand of animal feed, but figured the same issue could occur with any brand. I cannot emphasize enough how careful a gardener has to be in order to avoid accidentally bringing in a product contaminated with one of these persistent herbicide residues. People generally think "it can't happen to me" until it happens to them. Even municipal compost obtained from local city composting facilities has been found to be contaminated at times with these herbicide residues because both golf courses and the grassy parts of city parks often are treated with them, and then the grass clippings carry the herbicide residue into the municipal composting facility. I like coir but haven't used it in as large of a percentage as you intend to use it. I assume you intend to regularly feed your plants with a water-soluble fertilizer since nothing in your soil-less mix contains enough of the nutrients your plants will need? I raise all kinds of plants, including tomatoes, peppers, lettuce and mesclun mixes in containers and you have to pay extra-careful attention to their nutritional needs since the frequent watering required (particularly in the hot summer months) to keep them well-watered will leach the nutrients out of the growing medium on a continuing basis. Dawn

Thanks for the welcome! I immediately went to check the soil pep when I read your comment. Luckily I didn't see any thing of what you describe, but I think I will screen it before making a big batch just in case. Thanks for the heads up! Also, the worm castings I am using is not what you see at the big box stores in the bag. This is literally 100% pure worm droppings with zero added compost or anything else. It's literally only a couple tablespoons per gallon. I'll attempt to post a picture of the bag from my phone. Therefore I'm still considering using peat in the mix. If anything, maybe I'll cut the compost ratio down to .5 making it a 3:1:1:.5 mixture. Will see.