Authored by Tim Barnes; Edited by Luke Barnes

Creating good soil is one of our goals here at the Shoppe. As such, this article will outline the soils that we blend for grass, plants, trees, and veggies. I’ll also explain what causes soil compaction, and offer some planting tips.

There are many opinions and ideas online on how to best blend and mix soils. A common pit-fall is becoming too concerned with the makeup of the soil or adding exotic ingredients to the mix, instead of merely focusing on what works. In my personal experience, after many years of mixing both failed and successful blends, I have come to the conclusion that the simpler you can make your soil – the better. In fact, most plants really don’t need all those complicated ingredients that many online sources talk about.

For example, most plants that one might see in a typical Salem or Dallas neighborhood are simply growing in the Willamette Valley’s native clay. Yet, I often see people that want to plant flowers, a shrub, a tree, etc. into a hole with non-native soil. This is not preferred, as the plant will be encouraged to only grow within the soil of that hole, in that quality, easy-for-roots-to-spread-in, loose-fill mixture. It’s much more important to properly plant the tree or shrub in a mixture of both native and added soil, blending the two together. Below, I will explain our soils, and how to successfully blend them in with the Willamette Valley’s native soil.

Fill Dirt – This is the base dirt that is included in all of our blends. Better known as sandy loam topsoil, this dirt is basically sand and clay. It comes off of the gravel belts at the river quarries, then is screened and dried. It’s a fairly neutral soil, approximately 6.4 to 6.8 on the pH Scale. It’s not effective as a growing medium, and when water is added, it will pack fairly hard – thus why other materials must be blended into this soil.

3 way 40% soil – Our 40% as an all-purpose soil, blended mainly for sod and grass seed. This has: 60% Sandy Loam Soil, 30% Compost, and 10% Aged Fine Fir. Till this blend into your on-site soil. Never just place it over the top and try to plant seed or sod – that will create a layer and will encourage roots to stop growing when they hit the native clay. It’s best to place a 3-4 inch layer over the native soil then till to at least 6 inches deep. If your only option is to place a layer over the top, then put down at least 6 inches of 40% soil, so the roots have room to grow.

3 way 60% soil – Our 60% is our all-purpose planting medium, and works great for ornamental trees and plants. It consists of: 40% Sandy Loam Soil, 50% Compost, and 10% Fine Aged Fir. There are a lot of organic materials in this blend, so it will shrink slightly. For example, if you’re building a mound, add about 20% for that decrease.

Cow Punch Soil – Created specifically for vegetables and similar plant materials. A blend of: 40% Sandy Loam Soil, 30% Compost, 20% Cow Peat, and 10% Aged Fine Fir. The key ingredient is the Cow Peat! What that is, is a cow manure run through a process that sterilizes and dries the product, creating a peat moss type of material with no contaminants. This product is as organic as it gets when you are cultivating your precious plants, from succulents, to marijuana, or simply (and most deliciously) for your garden vegetables. Cow Peat also serves as a natural, completely organic nitrogen source.

Cow Punch with Pumice – This blend is the same as the above, only with the added benefit of pumice for enhanced soil drainage. Use this blend of Cow Punch with Pumice for planter boxes, vegetables, or wherever you want all the growing benefits of Cow Punch but with increased drainage.

So there you have the blends that we make here at the Landscape Shoppe. But, before I get into planting tips, I want to make an important clarification about the all-too-common problem of soils becoming over compacted.

Soil Compaction – All soil will compact. If it didn’t, it would basically just be sand. Our soils (just like all soils) will compact depending on a lot of factors. Mainly, it’s water that compacts the soil. The more you water the soil, the more it wants to compact. Essentially, it’s the weight of the water on that soil, daily, that will separate the blends, and cause that dreaded compaction. It’s a two sided coin: one side bad, the other good. Water your plants and they grow but in so doing you also water the soil, and it thus compacts.

To alleviate that soil compaction, try tilling larger areas – the vast majority of farmers do this for good reason! – or spading smaller areas using a shovel, pick, or similar tool to loosen soils around root zones. My own garden has almost the same exact Cow Punch Blend I added five years ago. Every spring, all I do to that old soil is: loosen, or otherwise break it up, add a little Potting Soil or Cow Peat Compost, then sit back and watch it grow great plants annually.

Some Planting Tips:

  • Trees and Plants – always dig your hole thee times as wide and twice as deep as the root-ball, or container, that the plant is in. Blend one of our soils into the onsite soil of the hole, or just about any other additive that will help break up the clay. Incorporate the clay into that soil blend because this is what the roots will eventually need to push out into. Next, add back into the hole half the blend that you dug out, lightly compacting it, so that the root crown is slightly above ground-level when finished planting. Stake trees, and/or larger plants for at least a full season so that the wind doesn’t tear at the new roots. Add mulch or bark on top of the root zone to help retain moisture.
  • When filling planters, use a product like our Cow Punch with Pumice to help with drainage. Another trick I’ve used over the years, is to line the bottom of the planter box with 3/8ths pea gravel. This will help drain out the water and keep the soil from clogging the drain holes in planters. Also, when digging trees you can add 1-1/2″ River Round to the bottom of the tree hole. Just dig the hole a little deeper and line the bottom with the round rock. This helps to allow water to percolate down through the hard pan of the soil table.