Soils & Natural Fertilizers
The Basics to Healthy Garden Soil:
If you haven't already amended your beds in the fall, don't fret.
Even though the weather is quite unsettled preparing your garden beds for the spring is essential and it can be done sooner than later. Now is the time to take stock of your soil condition well ahead of the planting season. We are super lucky that there isn't a ton of snow laying around covering our beds and as the temperatures begin to climb even those north sides will begin to let go of winters icy grip. So, if you can take a look at your beds and decide what they might need now you can have it done ahead of planting. If you're like me you forgot which beds got the garlic last fall, snoop carefully. They are in there!
How do you know if your beds need amending? Best not to guess. The reason for this is that we can't just look a soil as plain old dirt because there's much more to it than that. It's actually a complex mixture of organic materials, minerals, and other nutrients. Water needs to be able to move through it along with air and the plants roots and it needs to be able to keep plants upright. This means, it has to be fertile and has to have a good condition of texture.
Fertility is its quality of a combination of nutrients, microbes and Ph levels that can effectively provide a healthy home to your plants.
Texture is the size and structure of the soil itself in particles and cohesiveness and its ability to hold water and air. Poor soil will never really properly maintain a plants best health even with fertilization, because nutrients alone are only part of a healthy garden bed.
A good soil is imperative for growing strong, well producing plants that are healthy enough to withstand pests and diseases. Regardless of whether you are starting from scratch or working in your own soil in an in-ground bed improving your soil is a constant practice. Your soil is like a website. It can be good for a period of time, but when things change or become stale it's time to improve what you have already done.
Living soil is what earth naturally is. It is made up of many differing organic mediums, microorganisms, fungi, bacteria, minerals and structures and even animals in the case of worms. A good balance between these portions is what it takes to have the healthiest of plants. Happy plants produce more, flowers, fruit, vegetables and foliage than plants that lack what they need.
Just like your plants need to be fed, so does your soil in order to provide a nourishing environment to grow your plants.
That being said, there is no real right nor wrong way to amend your soil, unless you are not adding to your soil at all, because that is the only wrong answer.
Your soil is basically a nutrient field for your plants. Think of a cow grazing a pasture. The soil feeds your plants, so the more fertile it is, the better for your plants. If the cow was grazing in a parking lot, how do you think it will do over a summer? So, it's the same with your plant material and organic material is key. Organic matter is anything that contains carbon compounds that were created by living organisms. Some examples are plant debris, shredded leaves, animal manure, and grass clippings.
These promote a bio diverse mix that also address aeration and drainage. Organic material improves soil structure, binding pollutants, and aiding in soil buffering which basically means the ability of your soils to resist changes in pH.
Adding organic material to your soil works because organisms in your soil break down organic matter and convert it into nutrient-rich humus. As organisms feed on the organic matter, they tunnel and create pockets and lighten the soil allowing air and water to reach the roots.
A soil that starts out as mostly heavy clay will compact easily. It may become waterlogged, or prevent air and water, along with the nutrients from reaching plant roots. So, amending your soil matters a lot here in Calgary as we have a very heavy clay-based soil.
Know what plants you want and where may help you decide what to use when it comes to amending your soil. For instance, grapes love a sandy well drained yet rich soil and potatoes don't like manure. So, it can be beneficial to know which plants like what amendments.
7 Straight Forward Methods to Improve Garden Soil
As noted, compost is number 1 on the list for good reason. If it's the only thing you do, at least do this. Let's add a couple more reasons why adding a compost is a good idea. It also helps retain water deep in the soil which is also super beneficial here on the windy prairies where rain can be scarce.
Compost also feeds earthworms and other microbial life in the soil. The worms will tunnel through the soil to improve aeration and drainage while leaving behind their castings to increase soil fertility.
If using one type of compost is good using two or three from other sources is even better. The microorganisms in each compost will be different from others, so share and mix composts for a vibrant soil.
Do a Soil Test
Like we said at the beginning, best not to guess. Tending to your soil is not one and done. Conduct a soil test every few years to determine what additional nutrients are needed to promote plant growth and production.
We have a couple of ways to test your soil through kits and or meters. Full laboratory results can be done through AGAT, but for some it may be cost prohibitive. You should be able to manage well enough via the soil testers that are readily available unless you are having real issues or just want to know.
A basic soil test gives readings of soil pH, nitrogen (N), phosphorus (P), potassium (K).
Once you recognize the nutrient deficiencies in your soil, you can add amendments for a boost of nutrients. For example, alfalfa meal can add nitrogen, phosphorus, and potassium to the soil. Worm castings are a great amendment for nitrogen. Bone meal provides phosphorus and calcium. Most often, a regular dose of all-purpose organic fertilizer is all that is needed.
Mulch Your Soil
Mulch is super beneficial for areas in your garden that it can be used effectively and a must for healthy garden soil and strong plants wherever it can be employed. If you take a walk in any wild area, you'll note that it stimulates natural growing conditions, retains soil moisture, keeps soil cool especially effective for plants that need cool roots like Clematis, and it can also prevent weed growth.
The mulch will slowly decompose and add organic matter to the soil to increase fertility.
Avoid Soil Compaction
Dig up and turn over any soil that has become hard and compacted. Doing so will allow water and nutrients to soak in and the soil that has become barren and dry. It's important to observe compacted soil because it makes it difficult for baby plant roots spread out in search of moisture and nutrients, if they can't the plants dehydrate and starve. Compact soil also impedes microbiological activity necessary to convert organic matter to nutrients that feed the plants.
Especially here our clay soil tends to compact easily with just the weight of winter snow and ice. Adding organic matter over time will balance the soil structure.
Note: while working in your beds and with your soil when it's too wet you can easily do the opposite of your goal and compact it. In spring, wait until the soil is dry enough so a handful of soil doesn't stick together.
Prevent soil compaction by staying off of it and out of it whenever possible.
Crop Rotate Every Year
Move your veggie crops yearly to a different spot in your garden. Planting in different locations prevents the exhaustion of nutrients and interrupts the cycles of pests and diseases.
A great example is potatoes. Potato pathogens like nematodes and fungi that can cause scabby skin patches on potatoes quickly increase in the soil during a single growing season. You may not see the dire results in one season, but planting in the same spot year after year will certainly be noticed. Disease spores and organisms will die out naturally if they are unable to feed on their preferred crop.
There is a rule of thumb that one can follow which is basically rotating crops so that the same family of vegetables are not planted in the same spot for more than three years. This gives your soil time to allow for these pathogens to die out naturally.
You can also swap in nitrogen fixers to these beds in off years to replenish the soil like pea and nasturtiums.
Grow Cover Crops
Cover crops are grown primarily to benefit the soil, but some of them can function double-duty by providing food too.
Kale, and other broad-leaf greens are ideal for use as cover crops and can be also eaten. Clover, ryegrass, legumes, and peas are also good cover crops in preparation for winter.
Plant a cover crop near the end of the garden season and allow it to remain in the garden over the winter. This provides protection of the soil from being eroded by heavy rain, winds, and snow melt-off. These kinds of plants can also prevent the soil from compacting, and stop weed growth during the warming of spring.
In spring turn in these plants which will break down in the soil adding even more organic materials.
Ok before we say this, do not use manure where you are going to plant potatoes. Manure, especially fresh manure, will bring out scab in the soil which will end up on the skins of the potato. All soils have it. It has to do with too high a PH in the soil. Watering regularly and the absence of manure will lessen the chance of getting scab.
Otherwise, there's nothing wrong with adding aged animal manure to improve garden soil health and fertility. Fresh manure is too hot and will burn plants, and may harbor pathogens harmful to humans like E. coli. It's important to compost or turn into the soil and allow it to decompose for several months before using it in your garden.
Take care that you know where you manure comes from as some manures can be contaminated with pesticides and herbicides and may cause damage in your vegetable garden. Once the manure is in your soil, it is difficult to eliminate.
There are many products and amendments that you can add to your soil, however, this can be a bit of a rabbit hole. The question is can there be too much? Yes, and that comes back to what types of plants you are growing. On the other hand, there are a few things that can be added to your soil. Some of the things that help plants depending on their situation would include, Myke (Root Rescue once a plant has been planted) and Earth Alive which are living organisms that are beneficial to plants. You can add earthworm castings for sure! Put a big handful in the hole before planting tomatoes for instance. Minerals may come as a bag of Rock dust or in a fertilizer that contains minerals and micronutrients which play a role in photosynthesis. You can add porous additives that can take and hold nutrients and the like such as charcoal or Zeolite. If your ground is packed hard gypsum helps break up the clay and diatomaceous earth can help control soil pests. Ten there's the usuals like vermiculite a perlite. As you can see there are lots of things you can do with your soil and yes, there are lots you can do to it to make it better. Prescribe to the ongoing process, rather than all at once. The charcoal will last a 1000 years, so a little bit every season won't break the bank and unless you turf your soil it will be there always.
Assess what you want to do and what you want to grow. Some things will do just great even if you don't do anything, except add N-P-K fertilizers, others will appreciate the efforts you go to.
Some soil tips:
Gypsum can be added to heavy clay soil to make it easier to dig in organic material.
Garden & Bed Soil Preparation
Ideally, soil preparation for the planting of seeds and seedlings will be done in the fall. If this is not possible, however, organic material, such as compost or manure, should be worked into the soil in the spring. This will help the soil retain moisture, improve drainage, add oxygen and improve root growth.
Fall Soil Preparation
- Remove all garden debris from planting site, and add to composter for future use.
- Spread layer of organic material several inches thick over area. Compost or manure is ideal for this.
- Turn organic material into existing soil using gardening fork.
Note: Large lumps should be left in the soil at this point. Frost helps to break soil into a less dense soil structure, ideal for plant growth and moisture retention.
- Turn again in the spring, shortly before planting. Break down large lumps of soil with a garden fork.
Note: Slow release fertilizer can be turned into the garden at
this point, if desired.
Spring Soil Preparation
- Remove all garden debris from planting site a few weeks before planting.
- Turn existing soil using gardening fork, breaking up lumps.
- Add 4-6" of organic material and turn over again.
Note: Gypsum can be added to heavy clay soil to make it easier to dig in organic material.