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Soil Selection – Get the Dirt on Dirt

Mar 26, 2024

Dirt is dirt, right?

Most of us know this isn’t true but at the same time, there are a lot of bagged soils on the market all aimed right at you…the gardener. How do you navigate all of these different bags? We would like to give you a reference for figuring out which soil or amendment will serve you best. Your Intention is the first consideration when trying to figure out which soil to use. What are you interested in growing? Are you growing a plant indoors or outside? Are your planting beds already established? Are you starting from scratch? All of these are questions to ask yourself and your answers will determine what kind of soil you need.  

Organic or Not

Deciding whether or not you want to use organic soil or potting mix will cut your thought process in half. Once you know the answer to this question, you’ve excluded lots of products. Organic soil is rich in nutrients from decomposed matter such as leaves, bark, and plants.  However, this doesn’t mean you’ll never have to feed your plants. Vegetables, in particular, are heavy feeders along with annual flowers that are meant to bloom profusely. Whether it’s important or not to you to be organic, there’s no denying that organic soils contain loads of special items. Some are super-enriching, made with seaweed, berries and even lobster and mussels. If you’re growing your own food for health and goodness, then it seems to make sense to plant your edibles organically.  

In a Container or in the Ground

The first thing to know is not to use soil from your garden in a container. If it’s good soil, then why not use it?

  • Drainage is different. Water draining down to a hole or two is completely different than water draining outward and down in the ground. Water does not drain well in regular soil when the outlet is small. This causes roots to drown rather than receive hydration.
  • Air is another reason. Potting mixes are made to be light. In fact, they aren’t really considered to be soil and are often referred to as “soil-less growing media”. These media (potting mixes) allow roots to move freely to establish themselves. They contain (in varying degrees) peat moss, vermiculite or perlite, and limestone. Some even contain earthworm castings and fungi for super nutrition.

Seed Starting

Use a lightweight potting mix meant for seed starting. No gimmicks here! Those little seeds have a lot of work to do and won’t appreciate trying to push their roots into something heavy and wet. In fact, they probably won’t do it. We suggest either Pro-Mix or a medium made specifically for seeding.  

Planting Trees & Shrubs

Here. we have an area of controversy. One school of thought promotes no use of amendments when planting trees and shrubs. The thinking is that the plant will benefit from finding everything it needs by searching right away, causing roots to move outward quickly. The other school of thought believes in amending the soil and feeding the roots during planting. If you’re inclined to add amendments, here’s what we suggest. After setting the plant in the planting hole, fill in with:

  • 1/3 the soil you removed when digging the hole
  • 1/3 peat moss
  • 1/3 compost

A slow-release plant food can also be added during planting. At Faddegon’s, we use Coast of Maine Penobscot mix for planting. It’s also what we suggest to our customers for new plantings, as our experience tells us your plant will have a better chance of thriving. Penobscot has everything already mixed in. It contains salmon and blueberry compost, tiny mussel shell fragments, peat and forest products. The shell fragments help aerate the soil and add texture. We also recommend adding Plant-Tone, Holly-Tone or Bio-Tone during planting.  

Planting Perennial & Annual Flowers in the Ground

Perennials and annuals can be treated in the same manner as trees and shrubs. They are just smaller!

  • 1/3 the soil you removed when digging the hole
  • 1/3 peat moss
  • 1/3 compost

Or use Coast of Maine Penobscot Blend. You may also want to add Plant-tone at this time.  

If you are creating an entirely new bed:

Take away any debris, sod, weeds, and stones from the area you want to use. A soil test is essential at this point since you’ll want to incorporate either sulfur or lime during soil cultivation if it’s needed. After this, when soil is moist but not wet, with a garden spade or fork, turn and loosen all of the soil to a depth of 12-14″. To that layer add 3-4″ of compost or aged manure along with the pH amendment if you needed it. Turn over the soil again so the amendments are well mixed. This process is important because it allows air into the soil which is important for small roots.  

Planting Vegetables in the Ground

When putting vegetable plants in the ground, your energy should first go into making certain your soil is suitably built up. This will determine the success or failure of edibles! Take away any debris, sod, weeds, and stones from the area you want to use. A soil test is essential at this point since you’ll want to incorporate either sulfur or lime during soil cultivation if it’s needed. After this, when soil is moist but not wet, with a garden spade or fork, turn and loosen all of the soil to a depth of 12-14″. To that layer add 3-4″ of compost or aged manure along with the pH amendment if you needed it. Turn over the soil again so the amendments are well mixed. This process is important because it allows air into the soil which is important for small roots. Many experts recommend using several sources of compost instead of just one. If the soil is terribly compacted and impossible to dig into, then a raised bed garden is probably your best bet.  

Planting Vegetables in Containers

Think of this as a small raised bed. The same soil “recipe” will apply. Soil from a garden bed or topsoil alone are both bad choices for reasons of drainage. Containers don’t disperse the water well. The idea is to keep the soil lighter than it would be in the ground so water won’t collect around the roots for too long. But…you do want to retain moisture too. Confusing? You bet! Until you’ve done it once or twice.

  • 60% high-quality topsoil
  • 30% compost
  • 10% lightweight potting mix

or

  • 50% potting mix
  • 50% rich compost

There are also mixes made specifically for planting vegetables in containers, containing everything needed in one bag.  

Amending Existing Planting Beds

Many times you’ll hear gardeners mention top-dressing their planting beds. What does this mean? Even when you have established garden beds, over time you may notice a little less vigor in small plants, or you may plant annuals time after time in the same spot. Eventually, it’s a good idea to replenish soil nutrients by “top-dressing”. This means turning over the top inch of soil and adding rich compost. The rain will do the rest! Plant roots will benefit from rejuvenated soil. Soil should be rich and loamy for planting. Your soil may be too sandy, allowing water to drain much too quickly so roots have a difficult time getting enough hydration. Conversely, if the soil has too much clay, it will be too heavy for roots to move through easily and it will also cause root rot because it will hold too much water. The solution for both situations is compost. Compost mixed into a depth of 8-12″ will provide moisture retention for sandy soil. Compost mixed into clay soil will provide aeration and drainage.

Re-potting Indoor Plants

A lightweight potting mix is ideal for this project. Heavy wet soils will quickly do your indoor plant in. Plant roots need air and quick drainage. Also, forget mixes with food added, as it will start you off not knowing when to feed your plant. Also, different plants have different nutrition needs, while potting mix with food doesn’t take that into account. When re-potting cactus, orchids or succulents you will do well to buy a medium meant for those plants in particular. Some plants, such as types of orchids don’t thrive in soil per se. They’re happier in a large porous material such as bark chunks.  

Lawn Repair or Renovation

Whether you want to over-seed an area of your lawn or completely renovate it, the soil is part of the equation. Topsoil is the best choice for these projects. More importantly, if growing lawn grass is the focus, a pH test is essential. Putting down topsoil and planting grass seed without adjusting the pH is like putting wax on a dirty floor. You’ll still have a problem.

Soil Glossary

Amendment – Any material that improves the soil for planting. Using lime, sulfur, bone meal, compost or any other material meant to enrich the soil. Compost – Broken down materials such as; bark, leaves, vegetative matter, grass clippings, or any number of other organic materials. The manure of various animals can also be composted as long as the animal is an herbivore and the manure is aged.

Humus – Technically, it is the end result of decomposition. Compost may still retain visible elements of material such as bark, but humus is so fine that the components cannot be identified. Most often, the words humus and compost are used interchangeably in gardening.

Loam – Considered to be the ideal planting soil with the ultimate fertility. It is an even balance of sand, silt, clay and humus.

Peat moss – Peat moss is formed when mosses and living matter decomposes in a bog. Dried and packaged for gardening, it quickly gains back its moisture retaining ability when in contact with water in the ground. It also provides air, space and texture to the soil.

pH – A simple test to find out the acidity or alkalinity of the soil. For growing, most often a range of 6.0 to 7.0 is considered ideal (there are exceptions for certain plants). If the soil is too alkaline or “basic”, the number will be higher. If the soil is too acidic, the number will be much lower. pH test kits are available at all garden centers.

 

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