Bear with me, a teeny bit of background first: I'm lucky enough to have talked my wife into letting me get a 16 x 24' high tunnel from Farmer's Friend for 2024. After two years of having my tomatoes rained out I really wanted a hoop house badly and my wife, being the fantastic lady she is, said to go for it. Once the three feet of snow currently decorating my property disappears in April or May I'll put the hoop house up. I'm going to use 12 inch x 12ft boards to build raised beds inside it. There will be two long beds of 40 inches (37 inches after subtracting the width of the wood) by 24 foot on the outer sides, and one smaller 40 inch x 18ft bed in the middle. This will allow two 36 inch paths between the beds, a very comfortable amount of working room.

I want to fill these raised beds with good media for the tomatoes and by my calculation I will need roughly 7.33 cubic yards to do so. In the past I have handmade a lot of raised bed soil with a roughly equal mix of coco coir, compost, and vermiculite, which I amend with Azomite, blood meal, bone meal, and alfalfa meal. I'm not sure there is anything particularly magical about this mix, but it has worked well for me for six years and is still going strong as long as I amend it every year. I've also been using rice hulls from Seven Springs for the last three years as a mulch for my existing beds. I really like the rice hulls as garden mulch. They keep the weeds away, stay firmly attached to the soil, and keep the soil light and fluffy as they get worked into the soil over the succeeding years. They also look nice. I'm a moderate fan of the rice hulls actually.

Now to my question. Things are a lot more expensive in 2024 than they used to be so I'm trying to figure out how to be cost savvy about filling these new beds. I'm wondering if I could substitute rice hulls for the vermiculite. Or substitute rice hulls for the coir. Or simply add some percentage of rice hulls to the overall mix. I've googled this and gotten mixed and limited information. Since the rice hulls are cheaper than either vermiculite or coir as of today they could be a more cost effective soil component (if they work well for that.) Or this could be a terrible idea. Any thoughts from anyone with experience in this? Alternatively, anyone got any great ideas in how to build 7.33 yards of premium tomato growing medium in 2024 in a cost savvy manner? Bear in mind, it doesn't make sense to cheap out on the media after springing for a hoop house. I'm not after the purely cheapest option, I'm after something that is really excellent for tomatoes but without being unreasonably stupid financially about it. I reckon some other people here have wrestled with similar issues and I'm wondering what the accumulated wisdom might be

Local access to any of the materials saves money, as a lot of the price is in shipping. I happened to find a local greenhouse operation that was listed as a dealer for fafard. Another year I bought a super sack of hummerts mix, which does contain rice hulls:

https://www.dynagreeninfo.com/product/d ... a-classic/

Kelloggs uses rice hulls in several of their mixes. I use and am satisfied with Amend.

Ingredients
Compost (rice hulls, recycled forest products, arbor fines, dairy manure, poultry manure), gypsum, dehydrated poultry manure, hydrolyzed feather meal
https://kellogggarden.com/products/kell ... egetables/

Also I like bark fines. There is not a lot of consistency with bark products even with the same provider. Some are not acceptable due to a large percentage of wood shavings and the same bark from the same provider on a different day can be exceptional. As a soil mixture I look for groundcover bark but terminology can vary.

Cole_Robbie wrote: ↑Sat Jan 20, 2024 3:07 pm Local access to any of the materials saves money, as a lot of the price is in shipping. I happened to find a local greenhouse operation that was listed as a dealer for fafard. Another year I bought a super sack of hummerts mix, which does contain rice hulls:

https://www.dynagreeninfo.com/product/d ... a-classic/

That's actually super helpful, thank you! The ingredient list nails my question pretty clearly. I appreciate your quick and useful feedback!

zeuspaul wrote: ↑Sat Jan 20, 2024 4:22 pm Kelloggs uses rice hulls in several of their mixes. I use and am satisfied with Amend.

Ingredients
Compost (rice hulls, recycled forest products, arbor fines, dairy manure, poultry manure), gypsum, dehydrated poultry manure, hydrolyzed feather meal
https://kellogggarden.com/products/kell ... egetables/

Also I like bark fines. There is not a lot of consistency with bark products even with the same provider. Some are not acceptable due to a large percentage of wood shavings and the same bark from the same provider on a different day can be exceptional. As a soil mixture I look for groundcover bark but terminology can vary.

The inconsistency of the bark fines is the issue for me too. It should be the answer as I live in the middle of a national forest but you're always rolling the dice on what you get. It's sad that bringing rice hulls from the South makes more sense to me than using the unlimited bark fines I can see from my back yard. But the rice hulls are useful, cheap, and 100 percent consistent. Thank you for showing me they are used in the Kellogg media too. That answers my question

Filling beds is expensive. I don't know how deep your are but it may worthwhile to put logs and branches on the bottom to decompose or a bail of straw or two. These are cheap and will help to fill the boxes and add nutrients as the decompose.

Other options as substitutes for vermiculite and perlite. Special Kitty Unscented Non-Clumping Natural Clay Litter, 40 lbs $9.68 available at Walmart. I think it is still good (doesn't turn to mush when wet but need to verify). Free if you use it for your cat. Floor dry available at Autozone (granular DE), a bit pricey. Pea gravel available in bulk at reasonable prices.

In addition to the above bulk coarse sharp sand. Available in bulk at builders supply by the yard.

And Peat Moss!

zeuspaul wrote: ↑Sun Jan 21, 2024 1:01 pm Other options as substitutes for vermiculite and perlite. Special Kitty Unscented Non-Clumping Natural Clay Litter, 40 lbs $9.68 available at Walmart. I think it is still good (doesn't turn to mush when wet but need to verify). Free if you use it for your cat. Floor dry available at Autozone (granular DE), a bit pricey. Pea gravel available in bulk at reasonable prices.

I like using that clay for my cacti and houseplants. Moler clay I think they call it. Unfortunately a lot of the UK cat litter brands have moved away from it now (lots of complaints of cats paws turning pink ) so it's harder to find. It's also sold as oil absorbent.