top of page
Lamar Shahbazian

Lessons From the Garden - Part 3 - Soil Health

A new-to-me garden book and continued experimentation in gardening lead me to write again, sharing lessons from my garden. I am building on this blog written in May two years ago and this one written last June. I am newly motivated to be a successful gardener because I have begun sharing produce more widely, going outside sharing with neighbors and friends to delivering my excess garden goods to Una Vida to share with the food insecure in our community.


When I visited my sister in Willits last October, we visited the thrift store hosted in the Senior Center and I picked up the book “How to Grow More Vegetables than you ever thought possible on less land than you can imagine” by John Jeavons. While that edition of the book was written many years ago, I found it fascinating! More information and an updated version of the book, as well as many other resources, are available on their website.


I read the book on our next plane flight and my mind was blown! I started jotting down ideas and sharing them with my gardening friends. Since then, I have been implementing these ideas and am excited to share the results. Best $3.95 I ever spent!


In case you need motivation to garden, here’s a quote from the staff at Ecology Action, the organization that has tasked itself with championing and teaching the biointensive method of growing.


“The homegrown tomato requires no fuel in its transport, no packaging to be sent to landfill, no political decisions about who will be allowed to work the fields or what level of pollutants is acceptable in our groundwater.”


It’s all about Soil Health


I will attempt to recap some of the main ideas in this blog, but I highly recommend getting a copy of the book and reading it for yourself. One of the quotes from this book that literally stopped me in my tracks was “Stop growing crops and start growing soils!!!” As stated in the book, healthy soil makes for healthy plants:

  • Healthy plants are better able to resist insects and diseases

  • Most insects look for sick plants

  • The best way to control insects is with healthy soil vs. poisons which will kill beneficial insect life

There are lots of ways to build soil health, but I’ll attempt to cover some of the main concepts here.


Compost


While this might be common sense to most, it wasn’t until I read this book that I really knew how important compost is. I have been making compost for years, but was pretty lackadaisical about it. I mostly composted our veggie waste, or non-weed plants that I pulled from the garden. While I had read that you’re supposed to layer in dry ingredients and keep it moist, lack of ready access and pure laziness kept me from doing a great job. Nonetheless, I would generate about one cubic yard of compost a year, and spread it on my beds before my spring planting. While there are many aspects to soil health, this one is very important, and since it takes awhile to build compost, I put this topic first.


Since reading this book, I realized that having ready access to high-quality compost is key. I ramped up efforts to make my own compost, and also started searching for high-quality sources. So far outside of my own garden compost, I am testing two other sources: 1) I obtained some goat manure/organic straw mix from a friend and 2) I purchased some organic compost from Grab N Grow. Both seem to be performing well. I put some of the goat manure/straw mixture in my compost bins, and within a month it had fully decomposed. I also mixed some into my raised beds, and when I turned under the soil to mix in my “green manure” crop (more on that later), I found all sorts of worms on the side that had goat manure. I am also testing it as a mulch on my raspberry beds, and will track the difference in crop yield.


After hearing from a neighbor that Grab N Grow compost is sometimes lacking in nitrogen, I tested it by planting seeds directly in it. They grew well, so I mixed it into my beds as one of my main amendments.


My advice is to build your own compost, but if you don’t have it initially, purchase some and use it. Some people use animal manure for this purpose, but it’s best if you compost it first. There are concerns listed in the book about using manure. For instance, some animals such as horses don’t digest their food enough and weed seeds will pass right through. I witnessed this first hand in my neighbor’s field which is now covered with some really nasty weed, purportedly from a food source the horses ate and inadvertently spread. It also makes sense to think about what else the animal was fed. For instance, when my friend offered me the goat manure, she was careful to tell me the straw was organic and the goats were not given chemicals in their diet (e.g. antibiotics). It never occurred to me that the manure you use might actually pollute your soil!

At the recommendation of the John Jeavons book, I obtained a home soil test kit and tested several of my beds. They all came back lacking nutrients, so I figure either I don’t know how to use the test well or I’ve been doing a really poor job with my prior compost method. To be on the safe side, I also obtained bagged soil conditioner and added it to each bed. This was at the recommendation of Harmony Farm Supply here in Petaluma. I thought I would be very scientific and figure out which nutrient was lacking and add specific natural amendments (again, based on recommendations in the book), but the worker at Harmony convinced me to go with a simpler approach to save time and money. I figure since I’m just getting started on this soil health business, that was good advice.


From the John Jeavon’s book, here are some other tips for building compost:


Composting is natural, you can think of it as return living things to the earth. In the ideal world, your garden would be a “closed loop system” where all waste from it is returned to it. With food composting we can get partway there, at least until someone figures out a good way to compost human waste! One of the things I hadn’t thought about is what happens when you discard waste from your land, such as tree leaves. The book refers to this as participating in “ag strip-mining”. I never thought about raking leaves and discarding them in that way before.


According to the chapter on compost, it results in 3 ways:

  1. Manures

    1. Earthworms are especially good to compare to the soil they inhabit. Castings have 5x nitrogen, 2x calcium, 7x phosphorous, and 11x potassium than the soil they inhabit.

  2. Decay of plant and animal bodies

  3. Roots, root hairs, microbial life

Some of the benefits of compost are that it improves the structure of the soil. It provides good aeration and water retention. It helps resist erosion and preserves nutrients. Organic acid makes nutrients more available to plants. At first, organic fertilizers may have to be purchased. Once this is done, the health of soil can be maintained with compost and crop rotation.


While the book contains a lot more information on the science and offers many ways to build compost enclosures, here is one of the recipes for compost:

  • 1/3 soil

  • 1/3 dry vegetation (high in carbon)

  • 1/3 wet vegetation (e.g. kitchen waste) – high in nitrogen

    • All kitchen waste except meat and lots of oily salad scraps. Be sure to include bones, tea leaves, coffee grounds, eggshells, and citrus rinds.

Other tips in the book:

  • Make sure the soil underneath is loosened for good drainage

  • Cover the wet ingredients with soil to reduce flies and odors

  • Water lightly so pile is evenly moist

  • Too little water decreases activity

  • Too much drowns the microbial life

According to the book, you shouldn’t need to turn your compost regularly. One turning at about 3 weeks can help, and it should be ready approximately two months later. Mine usually takes longer than that so I’ll be interested to see if that changes with my new approach.


I’ve never thought about putting compost bins under trees, but the book says that ideally compost bins are situated under deciduous oak trees or other deciduous trees (but not under eucalyptus or walnut). Small tree branches can be composted by will take longer (2 years). It is best to put them in a separate pile.


Once your soil is healthy, at most you should add 1” of compost to soil for each new crop.

Some people use sheet composting, which is the practice of spreading uncomposted organic materials over the soil and then diging them into the soil where they decompose. The disadvantage of this is that soil bacteria tie up the nitrogen until decomposition has occurred, making it unavailable for plants. So you shouldn’t plant for 3 months if you use this approach. Sheet composting is beneficial if it is used during the winter in cold areas, because the tie-up prevents the nitrogen from leaching out during winter rains.


One of the other tips I read in the book is that one should avoid redwood compost because it can contain growth inhibitors that keep seeds from germinating or plants from growing well.


Some things I’ve learned from my own compost bins:

  • It’s handy to have three side by side. I usually have one as the “active bin” where I am dumping food waste, one that is halfway there that I turned from the first one last time, and one that is almost ready to use. I am not very regular about turning them, usually just once or twice a year.

  • Mine were initially set on bare soil, which they say above helps with drainage. Because we have gophers in our area, I found they were tunneling up and quite enjoying the bounty in my compost bin without me even realizing it. After that I put square pavers leftover from another project on the bottom of my bins, but if I were starting from scratch I would figure out a better way to secure the bottom.

  • We have wire (hardware cloth) on the sides, which allows for good aeration. The front has three 1x6” boards that can be removed as needed to turn or remove compost. This is very handy as it keeps the compost contained and the area is generally neat, but it gets the air it needs and I have access when I need it.

  • One of the things I’ve noticed since beginning my vermiculture experiment is that when I pay attention to where I find worms, they are usually in the active bin, and they especially like dry ingredients such as egg shells, cardboard, egg cartons, straw, or even small pieces of wood. Since I now have a much better understanding of the value of worms and am learning what they like, I am even more motivated to make my compost a balanced mix of dry and wet ingredients.

  • It never occurred to me to add dirt to compost! It would certainly help it break down faster, and I’ve found that since I’ve been amending my beds I often have soil that I’ve removed that I can use for this. One lesson that I’m still working on is the type of storage container for my extra dirt. Last year when I built my new flower bed, I put the extra dirt in a 33 gallon trash can. Do you think I can move it now? Especially after I neglected to put the lid on and it filled with water!!! Dumb! Even the 15 gallon black pots I used this year were too heavy once the soil got wet. As always, I continue to learn. My plan is to move them using a dolly to a place near my compost bin, so I can regularly layer in my extra dirt.

My goal is to produce enough of my own compost to sustain the needs of my garden.


Cover Crops


Cover crops are plants that are not harvested for food; rather, they are turned back over into the soil at the end of their growing season so that nutrients are added to the soil as they decompose. So, cover crops are grown not for your food, but for the soil's food. In the past, I’ve grown cover crops in the winter with the goal of “fixing nitrogen” in the soil. Just as the crop starts going to seed you cut it down and let it decompose. Local nurseries and seed companies sell cover crop seeds. I’ve used one called “green manure” from Harmony, which I believe is mainly fava beans and vetch. Other cover crops include clover, alfalfa, peas or other legumes. They are rich in nitrogen so they boost the level of this nutrient in the soil without one’s having to resort to the purchase of fertilizers. They decompose rapidly and planting can usually follow one month after plants are dug in. The disadvantage of cover crops is that the land is out of production during cover crop growth and decomposition. Additionally, green manures only produce about ¼ the amount of CARBON in a given area that carbonaceous compost crops do, and carbon in the form of humus is the most limiting and essential element in maintaining sustainable soil fertility. This year, I plan to experiment with a crop that can be harvested to add more carbon to my compost bin.


Fertilization


As in other cases, I’ve dallied in the use of fertilizers, and haven’t really paid a lot of attention to what I was using, relying on packaging to tell me what to buy for vegetables vs. citrus vs. flowers. I’ve started paying a lot more attention to what I’m putting in the soil, and have learned a lot in the last year. The goal of fertilizers is to build up nutrients to the proper level, especially initially when you may have not been composting or are trying to “repair” your soil. Once your soil is healthy, you should be able to maintain its health by composting properly.


As I mentioned above, I tried a home soil test but it indicated all my raised beds were short of nutrients. I believe that, since the soil has been there for 20+ years with little or no amendment. I had noticed that certain crops weren’t growing well, so started to pay more attention to soil health in general, and experimenting with companion planting and crop rotation (more on that later). I have not yet “bitten the bullet” to get a lab to test my soil, but I read that while soil tests cost money they can actually save you money because you don’t spend money on unnecessary fertilizers.

Here is some basic information on the main categories of soil nutrients: N, P, and K:

  • N – Nitrogen – contains proteins, is a food source in compost piles, and causes green growth

  • P – Phosphorus – gives plants energy and is necessary for the growth of flowers and seeds

  • K - Potash – aids in protein synthesis and the translocation of carbohydrates to build strong stems

Professional farmers are highly proficient at making sure the right fertilizer is applied at the right time. For instance, if you use a fertilizer that is high in nitrogen, you might get green growth but little or no flowers or fruit. So you can’t really use “one size fits all” as it relates to fertilizers. Another area where I have a lot to learn, but here’s a synopsis.

N-P-K are the three numbers on fertilizer you buy.

In the book, there is a complete list of the materials you can use to increase the nutrients in your soil. Different amendments are higher or lower in N-P-K, and last for different amounts of time in the soil. I was becoming overwhelmed by all the information in this section, so in the interest of saving time and money and making SOME improvement, I used a general soil conditioner. But in case you’re interested, here is some information extracted from the book:

  • Alfalfa meal – provides N,K lasts 3-4 mos

  • Blood meal – High N, can burn plants, use < 3 lb for 100 sq ft or wait two weeks

  • Hoof and horn meal – high N – slow releases – last 12 mos

  • Fish meal – good N and P – lasts 6-8 mos

  • Phosphate rock – good P - lasts 3-5 years

  • Potassium – wood ash – lasts 6 mos, use 1-3/4 qt per 100 sq ft

    • Alkaline – use with care if pH> 6.5

    • Aids in insect control, flavor enhancer for tomatoes and lettuce

    • Store in covered container until used

    • Exposure to air destroys the nutrient value

Many people think that adding manure is the solution to fertilization, but you have to be careful. In this book, they mainly cover the biointensive method, which tends to not rely on manure. It’s considered a good source of organic matter but the nutrient value will depend on proper management of the curing process and on the amount of straw or sawdust in the manure.

  • It is best to use manure that contains little undecomposed sawdust.

  • Manures that don’t contain much sawdust or straw can contain excess salt and imbalanced ratios of NPK. Biointensive (BI) methods recommend only using manure as an alternative to compost only when compost is not available. Aged manure may be substituted the first year when compost is not available.

  • Keep in mind that the use of manure requires much more growing space to support the needs of the animal. For example, a steer needs 500 sq ft to produce manure of your 100 sq ft bed. On the other hand, growing a compost crop only requires 100 sq ft.

  • There’s actually a chart in the book that shows amounts of N-P-K in fertilizer by animal!

One of the big buzz words these days is “sustainability”. If you think about it, the demand for organic fertilizers is growing, and supply is decreasing. Compost can be produced in sustainable ways by a healthy garden, so that’s one of the many reasons why I think it’s such an important topic.


Crop Rotation


One of the natural ways to keep your soil healthy is to rotate crops. If you think about it, this makes sense, since different plants give and take different things to the soil. If you have an infection of some sort, it’s more likely to affect the next crop if planted in the same space. There are different ways of rotating crops. For instance, you can do it over time, so that you are planting crops at different times of the year in the same space that have different needs, or even from year to year. You can also plant crops with different needs together, so that you are rotating crops in the same space. I have a lot more to learn on this topic, so will plan to share that in a future blog.


Companion Planting


I first heard about companion planting from a book I bought at a yard sale years ago. When I went back to reread it, I realized it was written so long ago that there were likely many more findings since then. If you think about it, testing what works vs. not in companion planting is HARD! How do you have a test vs. control in the process? How do you measure “success”? What I’ve done so far is reference various charts on companion planting, taking note of the crops I actually plant, and noting what they like to be next to vs. what they DON’T like to be next to, and try to plan my garden using those methods. As for other things I’m learning, it can be a bit overwhelming. The chart I used originally was in an annual Farmer’s Almanac, so I refer you to this article for more information.


Here’s another chart for quick reference.

I’ll summarize the highlights of companion planting so you understand why it’s worth the bother:


From the article above, here are 7 Benefits of Companion Planting:

  1. Deterring pests: Certain plants act as insect repellents or deter critters.

  2. Attracting beneficials: Some plants also attract beneficial insects.

  3. Shade regulation: Large plants provide shade for smaller plants in need of sun protection. For example, corn shades lettuce.

  4. Natural supports: Tall plants, like corn and sunflowers, can support lower-growing, sprawling crops such as cucumbers and peas.

  5. Improved plant health: When one plant absorbs certain substances from the soil, it may change the soil biochemistry in favor of nearby plants.

  6. Improving soil fertility: Some crops, like beans, peas, and other legumes, help to make nitrogen more available in the soil. Similarly, plants with long taproots, like burdock, bring up nutrients from deep in the soil, enriching the topsoil to the benefit of shallow-rooted plants.

  7. Weed suppression: Planting sprawling crops like potatoes with tall, upright plants minimizes open areas, where weeds typically take hold.

What I’ve learned in my own companion planting experiments, is that it’s okay and actually GOOD to mix flowers and vegetables. For some reason I always kept them in separate beds historically.


I had good success in growing nasturtiums and marigolds from seed and mixed them in with my vegetable beds, trying to pair them according to the chart. One of the things I learned is that nasturtiums reseed themselves like mad, so I will likely ALWAYS have nasturtiums in my garden now.


I also learned that it’s good to pay attention to the COLOR of the fruit you are hoping to harvest and the flowers you are planting. Last year I had yellow and orange nasturtiums happily winding their way through my Sungold cherry tomatoes, but unfortunately I was fooled a number of times thinking a nasturtium bloom was a ripe tomato!


I have definitely seen a decrease in the number of pests in my garden in the last few years, except for earwigs which are still the bane of my existence. So I think some of the methods I’m trying are paying off, but as always there is more to learn!

67 views0 comments

Recent Posts

See All

Comments


bottom of page