Sure you can. Re:amendments - I’d first mix in some good compost and aeration to make sure it drains nicely. Then I’d mix in some kelp meal, chicken manure pellets, a bit of lime. J
i use it . very good soil. no need to add perlite . just use nutrients as you would any other soil all set .
I would add some ground garden lime to the mix. Promix goes acidic the longer your in it. And depending on how old the bag is it can go there pretty fast. Just my opinion from growing in promix for years, im pretty tired of buying old bags and i am in the process of changing to coco. Good luck, great plants can be grown in promix just watch your runoff ph.
Promix is a combination of peat, sphagnum moss, coconut coir and perlite so it's pretty well aerated already. Some blends they sell contains time release fertilizers kind of like Miracle Gro. Just read the labels. If you are shopping there are products better for soil grows. I use Fox Farms Ocean Harvest, which contains nutrients but they are all organic.
HP is the High Porosity version. It's 30% perlite in the box. It's the only promix that I would consider using straight and not mixing more perlite with. I use Sunshine promix 4 which is much lower in perlite and I mix in an additional 15% or so of precision perlite course. The best application of promix is to use it as a hydro medium like coco and bottle feed it. I use it as an alternate method next to my DWC plants. The promix plants get the same feed. Actually my largest harvest to date was a promix plant in a 7 gallon smart pot with 15oz's. It's beat out DWC on some strains. I consider it superior to coco because it's less picky with PH and drying out. It behaves more like traditional soil but has much of the benefits of coco. It's one of the best rookie hydro methods if not the best. So easy. Just feed light and often. It has a small amount of starter nutrients in it so you can give a plant just water for a few days but that will quickly wash out. It's also used as a base for mixing in amendments and compost when construction your own soil. It works quite well for that I'm told.
I just started mixing in extra dolomite lime even though promix comes with it. Just start top dressing a few tsps every couple of feedings after about the first month or so. The lime is what corrects the ph so it burns off over time. The other mineral I've been wanting to get and mix in is langbeinite. 0-0-22. Time released potassium. Cannabis loves potassium. It would be nice to have some built in to fight deficiencies but being in organic form it won't burn.
I tried to amend it and add it during the last month to save a few plants but dont like guessing how much to add, cant take it back so i said "fuck it" and im giving coco a try. Ive had many successful promix grows but the last few years ive seen poorer and poorer promix. Hopefully coco will be nice to me.
I've never had a problem with promix late in the grow. Just add more cal/mag once the dolomite lime is depleted. That's all it is. Organic slow release cal/mag. Once a plant is established the promix is basically a container for the root ball. The plant's health is more determined on the hydro feed you give it and water quality. I've had way more issues keeping DWC plants healthy. The promix plants don't even need an airstone.
TBone turned me into ProMix Sunshine #4 and I am so glad I made the switch. I am currently growing the largest plants I’ve ever grown. They grow at about a 40% faster rate in the ProMix than they ever did in the CocoLoco I was using. TBone— I added dolomite lime when I started using the ProMix...but you didn’t say anything about adding more dolomite lime lol I should be adding dolomite lime every week as a top dress? “Tyranny anywhere is a threat to freedom everywhere.” — someone awesome
I’ve never added lime to my advance mix 4. Been reusing it for 4-5 grow now. I did add extra perlite and pumice.
I don't add more. I just use a cal/mag supplement. I just add that to help with ph buffering and some cal/mag during the grow but I typically have to supplement it anyway. Probably has to do with the rainwater I use for a base at 0ppm. I don't think it will hurt but dolomite lime takes a long time to break down. I would rather use a calmag supp as the grow goes on then trying to satisfy cal/mag needs with just the dolomite lime. It takes too long to break down and with leds the demand for cal/mag is 25% higher then HPS at least depending on strain, light intensity, and how much your base water has to start with.
The main reason I add more lime is I water the mix down with about 20% extra perlite and I also don't use ground source water so mine will tend to consume the dolomite lime faster then other gardens. It never has hurt to add more. It's cheap insurance and will never burn the plant.
Copy that. Pro-Mix has recaptured my love for growing. I was so frustrated growing in soil. “Tyranny anywhere is a threat to freedom everywhere.” — someone awesome
To be more clear this thread is about promix HP. I don't use that. It's promix brand high porosity. The Promix HP already is 30% perlite. It can be used quite successfully right out of the bag. I use sunshine promix 4. It's a different brand with a different blend of ingredients. I can get it way cheaper then Promix brand HP. That's the main reason I use that brand. I add 20% extra course perlite and after I do that and 1tbsp of dolomite lime extra per gallon I consider it equal to promix HP. Promix HP is widely considered among promix growers as the best stuff you can buy right off the shelf and use. All other blends need a little tweaking to have proper drainage and to resist compaction over time.
I also like to add extra dolomite lime because if you look into promix much it is a peat based grow medium. Peat is the first ingredient. Peat is one of the oldest hydroponic mediums. It is well known that you have to "lime" your peat to keep the ph in the correct range for plant growing. Part of why I add it is to make sure that the promix company that blended it added enough so my ph won't get too off once it dissolves.