I need a recipe for Soil layering for raised planter / containers

I have raised planters being build this fall. I need to decide on what soil mixture goes inside. I am going to plant blueberries and perhaps a cherry if plum tree in the raised planter. The planters will be open down to the ground soil. I heard of the lasagna method ( sticks, compost, leaves, loam…) I am in the northeast 6b coastal. Thanks in advance.

I use mels mix for general gardening which is 1/3 compost, 1/3 peat and 1/3 vermiculite.
If your planters are deep, fill the bottoms with logs.
For blueberries I use 1/2 peat, 1/2 sandy loam with some vermiculite.

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Take into account that all organic matter you put into the mix (compost, leaves, etc.) will disintegrate over time and the soil in the planter will sink by the respective volume. No problem for a vegetable garden since you can add more soil mix every year, but not good for perennials, especially trees, since you cannot bury the root ball of a sunken tree.

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Re: Lasagna gardening. The thing about using cardboard as a kind of weed barrier (for one season) worked surprisingly well for me. Otherwise I didn’t see much value to it except to delay things.

I’m sure the “Mel’s Mix” would work very well. The el cheapo “Topsoil “ they sell at the big box stores works and is commonly used for this purpose. It appears to be decomposed sawdust sand and manure to me. You might want to add some vermiculite or something to keep it from compacting.

Look into using bio-char.
If you find it of use you still have time to start making batches.
You can use the larger chunks at the bottom and mix in the smaller pieces as you layer.