02 Jan 2011

Organic Fertilizer for Vegans

vegan dinner
Yum! Grow a healthy vegan meal

Organic gardening – or at least, organic fertilizer – appeals to most vegetable gardeners. In fact, one of the chief reasons for growing vegetables is to have a ready supply of healthy, natural food right outside your door.

But for the vegan (or any type of vegetarian) gardener, the ingredients in a balanced organic fertilizer may be even more of a horror than those found at the local garden center.

What’s the solution? Mix your own vegan organic fertilizer!  

It is easy and inexpensive if you buy in bulk.

Let’s look at the mixing formula first – then we can look at each component. This formula is adapted from Steve Solomon’s Complete Organic Fertilizer and from the Vegan Organic Mix recommended by The Garden Shed in the 1990’s.


2 parts screened worm castings or compost
4 parts “fast” release nitrogen derived from plants (soybean meal, alfalfa meal, cottonseed meal)
1/2 part slow release phosphorus – derived from minerals (soft rock phosphate)
1 part “fast” release potassium derived from plant material (north sea kelp meal)
1/2 part “slow” release potassium dervived from minerals (greensand)
1/2 part trace minerals (crushed rock/ Rado Rock/ granite meal)

For outdoor beds, add well rotted compost to the planting area at a rate of 1 cubic foot per 10 square feet.

I try to include more than one source for each macronutrient (N-P-K). This can help balance the release times of the fertilizer and keep it working all season. Of course,”quick” and “slow” are relative terms since most organic fertilizers are not water soluable.

And here’s the beauty of organic fertilizers – we are trying to achieve a balanced mix that will feed the soil, not a chemical formula that can pass the Department of Ag inspector’s test. If you know your soil will benefit from a little more kelp and compost – add them! Building healthy soil is an ongoing process requiring observation and trial and error.

This recipe is by volume – as long as you use the same measure for each ingredient, you’ll be OK. I use it at the rate of approximately 5 lbs per 100 sqare feet – but I had to find a scale and weigh my bucket to determine that. Adding this type of fertilizer by volume (i.e., this pail size for this bed) rather than by weight is perfectly safe.


Start with Nitrogen. Nitrogen is essential for leafy, green growth. It is also one of the most soluable fertilizer components. In organic fertilizers, nitrogen is introduced either through decomposing plant material (like alfalfa meal) or through a slaughterhouse by-product like blood meal.

You already know we’ll pass on the bloodmeal, so which plant source is best? I like to use alfalfa meal, if I can find a trusted source.  (Down To Earth from Eugene, Oregon sells a high quality alfalfa meal.) Don’t use the alfalfa sold as rabbit pellets. It has probably been sprayed with chemical pesticides. By the same token, also be wary of alfalfa meal sold as a rose fertilizer. Rose growers are not necessarily organic growers. 

Alfalfa has many benefits besides its nitrogen content. Earthworms are attracted to it – and there are few gardeners as talented as earthworms when it comes to building healthy soil. Alfalfa is also an excellent bio-activator for compost.

Soy meal is another high quality source of nitrogen. You can combine alfalfa meal and soybean meal to give variety to your nutrients.

Cottonseed meal has lately fallen out of favor with organic growers since cotton is so heavily sprayed with pesticides. According to most experts, the pesticides themselves are mainly trapped in the cottonseed oil, rather than the meal, so cottonseed meal should be safe for use in organic gardens. However, organic growers have been registering their displeasure at the level of pesticide use by avoiding cottonseed meal.

There aren’t many non-animal sources of Phosphorous. Once we drop bonemeal and fishmeal from the list, we are prettyt much limited to rock phosphate. Rock Phosphate can be an excellent fertilizer, and it should be worked into the soil of every garden. However, be aware that it may take several seasons to break down completely. If you can mix Hard Rock Phosphate and Soft Rock Phosphate together, you may have a more balanced fertilizer. Talk to your supplier about the source of the rock phosphate. It may be contaminated with other mining waste you want to avoid.

Potassium (or potash) can be readily found in both slow mineral and fast release plant form.

The #1 source for potash is nature’s miracle plant – kelp. Don’t skimp on the kelp meal. It is not always necessary to buy the highest quality, most expensive, North Sea Kelp Meal – but you do want your kelp to come from a known source.

Your retailer should know something about the origin of the product. Try not to buy kelp that comes from endangered kelp beds. Stay away from kelp that was harvested from harbors and shipping lanes: it is likely to be contaminated with diesel, at a minimum.

If you can’t afford Norwegian Kelp Meal, look for a good quality Asian Kelp Meal. You might find it for half the price of the Norwegian Kelp – with no noticeable compromise in results.

Kelp Meal is going to give your plants a ready source of potassium, for general, robust health. It also supplies abundant micronutrients and minerals for the microbial life in your soil. Without a doubt, a generous helping of kelp is one of the best things you can add to your soil.

For a slow release potassium – and slow in this case means years – try greensand. This seabed mineral not only supplies potash and micronutrients, it helps break up compaction in heavy clay soil and it absorbs moisture, reducing the need to water.

You may or may not have to add lime to your soil. This can vary from plot to plot in the same garden – and can certainly vary with the different requirements of different plants. You can test your soil pH with an inexpensive kit before adding lime.

Your final ingredient is rock dust. Most people don’t think of rocks as fertilizer – but they are the best source of minerals for organic gardens. Of course, you can’t just toss in some stones and call it good. You want finely ground – in fact, ground to dust – rock with a high mineral content. Granite dust is good. Glacial rock dust is excellent. As always – be responsible with your sourcing. Do not damage the natural environment to improve your own little plot of land.

That’s it. All these ingredients (with the debateable exception of worm castings,  which you can skip) are animal-by- product-free fertilizers and minerals, acceptable to vegetarians of every stripe. Each adds something unique to the soil structure. Microbes, worms, and other life in your soil – in addition to your plants – will all take something from the soil amendments. Mix it all together in a wheelbarrow and fork it into the top 6 inches of soil. Add compost. Water with a liquid kelp or a compost tea at least once a month.

Do this every season and you will have noticably tastier, nutrient rich vegetables, high in vitamins and minerals, as well as healthy soil.

Photograph by Fuzzcat Photo released under Creative Commons License

13 Apr 2010

How To Read A Fertilizer Label

Down To earth Multi-Purpose Fertilizer
A balanced, multi-purpose fertilizer

Every gardener has seen the three big numbers on the front of a fertilizer bag or box.

Most know what the numbers stand for (in order): Nitrogen – Phosphorus – Potassium, also known as N-P-K.

These ingredients are always listed in this same order.

The higher the number, the higher the water-soluble percentage of that ingredient in the fertilizer. For instance, Sulphate of Ammonia, rated at 21-0-0, is 21% soluble nitrogen. It contains no potassium or phosphorus.  On the other hand, something like SuperPhosphate, rated at 0-20-0 contains 20% phosphorus but no nitrogen or potassium.

Why should we care specifically about these three elements over all others? What exactly do they do?

  • Nitrogen promotes green growth above the soil.
  • Phosphorus promotes flowering, blooming, and root growth
  • Potassium promotes general vigor with compact, robust growth.

These attributes are sometimes learned by the memory aid, “Up, Down, All-Around.”


So do higher numbers equal better fertilizers?


Healthy plants grow in healthy soil.

fertilizer burn
Fertilizer Burn

Soil amendments and fertilizers certainly play a role – sometimes the crucial role – in promoting plant growth. But highly soluble, super-concentrated ferilizers can actually harm plants, the soil, soil microbes, and the environment.

Fast release nitrogen can burn seedlings. You’ve probably seen plants with brown edges on their leaves. That can be a sign of fertilizer burn.

Further, highly soluable fertilizers wash through the soil quickly, leaving little or no nutrients behind for continued growth.

And finally, high concentrations of phosphorus run-off can pollute water and kill fish.


While N-P-K gets all the glory on the label, other ingredients, such as minerals and trace elements are just as important to the health of your plants. Use the Big Three numbers on the front of the bag as a guide.

Then turn the bag or box over and look at the rest of the ingredients. A long list of nothing but unpronouncable chemicals is unlikely to promote a healthy environment. On the other hand, trace minerals and other insoluble elements will bind with the organic matter in your soil. They are unlikely to wash out as quickly, and so may slowly release nutrients to your plants throughout the growing season.


compost worms
Nature's Perfect Gardeners

Soil rich in organic matter will also be rich in life – most clearly illustrated by the presence of earthworms. Burning, quick release fertilizers kill worms, leaving you with dead soil that demands constant re-fertilization. Compost and minerals, in contrast, provide food for the worms, who turn it into one of nature’s richest fertilizers: worm castings.

Organic fertilizers tend to have “lower numbers” than chemical fertilizers, in part because organics are less water soluble. And yet, that very fact gives them an edge in promoting sturdy, compact plants with deep roots – plants more able to resist insects and disease.


Do you have to be 100% organic to have a healthy garden? No, of course not.

But you’ll find that shifting your focus to organics will, over time, build healthier soil. As your soil improves, your plants will improve. You’ll be less tempted to reach for pesticides, and the beneficial insect population will be able to do its part in keeping insect damage down.