By: Steve Jones, scvrose[at]aol[dot]com
Probably the most overlooked fertilizers are those that have an organic background. Some are plant by-products, others are from animals. I have worked with animals and raised crops on a farm for several years and saw the use of all the animal and plant by-products in various applications. You would be amazed that they process all parts of an animal into usable products. My mom grew up on a farm and with little food storage and no refrigeration, and she told me that they would slaughter an animal and eat every part of the animal including the moo, oink and squeal. I haven’t figured out where those go in the processing methods used today.
Few parts of an animal or plant are left for waste. Most find their way into some sort of a fertilizer or by-product. With animals, their manures are excellent sources of nitrogen and other minor nutrients. Often the makeup of the manure depends on what the animal is fed. If fed a lot of grain like corn, the manures will contain a lot of the undigested and partially digested feed. A common problem is with steer manure, which comes mostly from scrapings from feed lotused for beef production. Special care needs to be taken with steer manure as it may contain high levels of salt, as most cattle love to lick salt blocks. Plus it might have high levels of urea salts.
Working on the dairy, I was in charge of scraping the pens and piling the beef and hog manures into big piles. The manure was left to dry and “age”. Eventually we spread it over our corn or oat fields to help boost the crops. Nothing at the dairy went to waste. The corn was completely ground up to form silage which is aged and when the process is stopped, it is fed to the cattle. The aerobic cooking of the feed is similar to composting. We often added a high nitrogen source into the feed to make it more easily digestible. We wanted a high TDN (Total Digestible Nitrogen) as it made better feed. Even the roots and stubs of the corn plants are tilled under to make fertilizer. When you buy alfalfa, the TDN is what dictates the price. For rose fertilizers, we only care about the amount of nitrogen and other nutrients in the material.
Chicken manure is an excellent source of nitrogen as well. The fresh manure is very odorous; however, many rosarians have been using composted chicken manure with great success. There is very little of the bad odor left after composting. On the farm you could smell for miles if anyone used chicken manure in their fields and were irrigating. The smell lasted for weeks. Bat and seabird guanos have been popular as an excellent source of phosphorous and nitrogen. The manure is farmed from bat caves and islands in Mexico and South America. Some of the deposits are prehistoric in age.
Horse manure is very good and if aged, makes for excellent mulch. It does not smell when wet and flies are not attracted to it. Most farmers and horse stables are happy to let you take as much manure as you wish.
A controversial source of manure in some products is digested and processed human waste. These products are pathogen free, but may contain heavy metals. Two common products are Milorganite and Kellogg’s. Most of the bagged manures, top soils, composts, etc. from large companies usually contain human waste if the source is not mentioned. Most of these factories are located near a sanitation plant and the “products” from the sanitation plant are sent by conveyor to the processing plant.
For those who are squeamish, you might avoid this next paragraph. If we lost an animal, or one was killed on the road, then a truck came by and picked them up and took them to the rendering plant. There is no truth that there is a Texas Department of Road Kill and Culinary Arts. Every part of the animal ends up in one product or another. Even old grease from restaurants like McDonald’s is sent to the rendering plant, as well as the remains from processing animals at slaughter houses.
At work I deal with about three rendering plants in the Los Angeles area in addition to one near where I lived on the farm in Central California. The dead animals are unloaded into a holding area. The hides are removed and sold to tanners. The remaining parts are sent to different areas and cookers. The “meat” usually ends up as animal by-products in pet food. Blood meal is dried and sold as such, which is an excellent source of nitrogen and is very fast acting. The bones are ground up and sold as bone meal, which is an excellent source of phosphorous and calcium. There is no truth to the tale that ‘mad cow disease’ will end up in any of these products. The fats from the oils and cooked meats end up as tallow, which is a fatty product. Most of the tallow ends up in products such as soap and cosmetics. Feathers are often ground and sold as feather meal, which is a medium to slow source of nitrogen. The problem is the wet bird smell is there when you wet it, but it soon dissipates.
When we harvested oats or barley for the grain, we cut the rest of the stalks and used them as straw and feed for the cattle. We also purchased bean straw, which is the leftover plant after harvesting the beans. Bean straw is especially high in many nutrients. All of these straws can be used by gardeners as mulch. Mulching helps control weeds and retain water in the soil. The straw will break down in time and add extra nutrients to the soil. The same can be said for many manures, and leaves from other plants, such as pine and oak. Composted plant material is excellent not only for mulch, but also to help break up soils while feeding the growing plants.
Fish meal is made from the leftover parts of fish and unusable fish like mackerel. The fish material is ground, oils extracted, and then cooked. Fish meal is an excellent source of nitrogen and proteins and is fast acting. There is some odor when using this product, so you will be the most popular person in your neighborhood, especially to all the cats.
Examples of other fertilizers from plant processing are cottonseed meal, alfalfa meal, kelp meal, and soybean meal. All are excellent sources of nitrogen, and cottonseed meal is acidic so you need to be careful using this product if you have acidic soil. We have mostly alkaline soil so it is not a problem to use here. Kelp meal is loaded with vitamins and micronutrients such as manganese, copper, zinc, etc. Kelp meal can be high in salt also, but there are several low salt products available.
Sawdust is often used as a mulch and soil conditioner, more so than for its nutritional value. It is low in nitrogen and to break down it needs to use more nitrogen. So fresh sawdust is not recommended, and it should be composted or aged. You can use it, but add a good nitrogen source along with the sawdust.
General Fertilizer Information
As with all chemical fertilizers, organic fertilizers are rated by the amount of nitrogen, phosphorous, and potassium (NPK) in them. Typically these contain lower amounts of NPK than most chemical fertilizers. Typical chemical fertilizers for roses are from 8-8-8 to 20-20-20. Some exhibitors will use a product higher in phosphorous, such as a 50. The number represents the amount of each material as total nitrogen, P2O5 and K2O. Most manures and plant materials are in the 2-2-2 range, and not likely to burn. These materials are generally slow release and make a great base under your mulch.
The best fertilizers have a good carbon to nitrogen (C:N) ratio. Ideally they should be 10:1. These break down quickly and require little help except from soil bacteria. Those low in carbon or nitrogen will need additional material of the lacking nutrient. For example, sawdust is low in nitrogen, thus to break down, it steals nitrogen from other sources. Green plant materials usually contain a high nitrogen content versus carbon, so they breakdown quickly and overdo the needs of the soil microbes. Straws on the other hand are mostly carbon and have very little nitrogen, so they take a long time to break down. It is best to mix both plant and animal materials so they can work off of each other. C:N ratios greater than 20 will not make the nitrogen generally available.
The Fertilizer Elements
Nitrogen is necessary for the plant to grow and for the foliage to be green. Nitrogen is necessary to produce proteins, which in turn make the plant stronger and aid in growth. Too much nitrogen can be as harmful as not enough. Most nitrogen products are fast acting and move through the soil quickly. There are several slow release organics that help a plant over a longer period of time. Both fast and slow release nitrogen should be fed to your roses. Nitrogen moves through he soil very quickly, so this needs to be replenished more often than other nutrients.
Phosphorous is needed for root growth, plant health, and more and better blooms. It is not fast moving through the soil so that is why adding phosphorous containing fertilizers, such as bone meal, to the planting hole is highly recommended. Phosphorous moves through the soil at a rate of one inch per year.
Potassium is needed for overall vigor of the plant. It is needed for plant health and resistance to diseases. There are three additional nutrients that plants need, but in a smaller amounts. Most soils have more than adequate amounts of these materials.
Calcium is needed to build strong plant membranes and help ward off toxic effects of other elements. Also needed to bind soil ions.
Magnesium is the central element of chlorophyll, the green in our plant. It is needed to convert sunshine into energy for the plant.
Sulfur is a component of many proteins, especially the amino acids needed for energy. There are several elements that are needed in tiny amounts. They are called micronutrients and include boron, copper, zinc and iron. Healthy soil that is high in organic matter usually contains plenty of these elements.
Plant By-product Fertilizers
The following is a list of many of the plant by-product fertilizers that are available from most nurseries and feed stores.
- Cottonseed Meal – A great feed for cattle and for the yard. It is acidic, so best used in alkaline soils like ours. It has a 7-3-2 analysis and is a slow nitrogen release.
- Kelp Meal – A good slow release material good for potassium and trace elements, especially manganese, boron, copper and zinc. Analysis at 1-0-2. A liquid form can be used to dip cuttings into for propagation.
- Alfalfa Meal – One of the best fertilizers for roses. Analysis at 2.5-1-1, it contains numerous vitamins, 16 amino acids, and proteins. The main ingredient, triacontanol, is a plant growth promoter. Use in an alfalfa tea formula or as a fertilizer under your mulch cover.
- Soybean Meal – Fairly new to the fertilizer market, this 7-2-1 material is a good source of slow release nitrogen. I need to try this next year in my mix.
- Straws – Most straws are low in nutrients, ranging from 0.6-0.2-1.1 for grain straws to 2.5-0.5-2.1 for alfalfa hay. Bean straw is in the middle. Straws are better used for mulches and soil amendments than fertilizers.
- Plant Shells – The shells from some plant seeds are gaining in popularity for use as mulches and soil conditioning. Cocoa shells have a 3-1-3 NPK but contain little other nutrients. The overall appearance of cocoa shells in the garden is why they are popular. Peanut shells are not very appealing as mulch and they contain a NPK of 1-1-1.
- Composts – Plant materials are composted to make a good soil conditioner and mulch. Not a high NPK value, but they are invaluable for taking care of household and yard waste. Homemade compost varies in NPK values, depending on the materials used, but they tend to be low, around 1-1-1. I use mushroom compost as mulch. It breaks down within the year and slowly feeds my roses. Mushroom compost has a NPK of 2-0.4-2.4, and a C:N ratio of around 10-15. The pH is around neutral, so it will not affect soil pH to a large extent. They have good water holding abilities as some of the make up is peat.
- Ashes – The by-product of burning wood and other plant material is a good source of potassium, with a NPK rating of 0-1-5. Ashes are very alkaline, so care needs to be taken if your soil pH is alkaline like ours. I prefer not to use ashes in our area for that reason.
Animal By-product Fertilizers
The following is a list of many of the animal by-product fertilizers that are available from most nurseries and feed stores.
- Blood Meal – Blood from animals, this high nitrogen, 12-0-0 fertilizer is fast acting. Great to use the week before a rose show for added green to leaves.
- Bone Meal – From ground animal bones, a great source of slow release phosphorous and calcium. A NPK of 3-15-0, it is great to use in the bottom of your planting hole.
- Feather Meal – This 12-0-0 fertilizer is grounded up feathers. A good source of slow release nitrogen. Some smell when first wet, but quickly dissipates.
- Bat and Seabird Guano – Harvested from caves and islands, this manure is varied depending on area. Some guanos test out around 8-4-1, while others are high in phosphorous, and can be around 3-10-1. Great for root growth and blooms.
- Fish Meal – A dry fish by product, fairly fast acting. Does have an odor, some products offer low odor fish meal. NPK at 10-6-0.
- Fish Emulsion - A liquid form of fish, it is tested at 5-1-1 and is a great fast acting nitrogen source to use on plants, especially before a show. Mini roses love this material, has a lot of vitamins, proteins, and trace elements. Most exhibitors use this in their fertilizing regiment. Make sure you mix it up according to directions. Applying directly to the plant without water will burn and possibly kill the plant.
- Manures – Most of the animal manures are low in NPK, usually 1-1-1 or less. They make a good fertilizer with low release nutrients, a good soil amendment, and good mulch. Sheep manures are higher in NPK with 1.4-0.5-1.2, and chicken manure is around 3-1.3-1.2. Rabbit manure is among the highest in nutrients with a NPK of 2-1.3-1.2.
- Sewer Sludge – Depends if it is digested or activated, NPK can range from 2-3-0 to 6-3-0. Commonly used in large packaged top soils, amendments, soil conditioners and mulches. Good all around fertilizer and soil conditioner. Some care needs to be taken from high metal contents.
- Animal Shells – I have seen a lot of animal shells for sale usually ground up into a powder. Oyster shells are quite common. Others include lobster, clams, etc. High levels of calcium, but the pH is normally very basic, so we shouldn’t use in our alkaline soil. Has low to no NPK value.
Most organic fertilizer mixes have a combination of the above materials. Consider using many of these materials in conjunction with your other fertilizers, as well as just by themselves.
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