Taking the research done for the hydroponics industry as an example, we can see that plants do need different ratios of nutrients at different stages in their life. I think hydroponics is unnatural and too much engineering but it definitely has its place when it comes to food production where there is no soil. Using the results of those researches and applying them in soil is our responsibility.
Where there is soil, it should be used and improved…
For the soil to provide balanced nutrients at different stages of a plant, it has to have a reserve of those nutrients abundantly at different depths or we should feed the soil at different stages specifically so that mycorrhiza and bacteria can process and feed the plants as required.
Let’s have a look at what plants need during different stages of their life.
Seed to Flowering – Baby
As an annual plant starts its life as seed it needs a minute amount of nitrogen as well as some protective barriers to prevent molding. The root also develops to absorb nutrients from soil. Until the stage of flowering, the main objective for the plant is to grow a maximum amount of stem, leaves and roots. Nitrogen and phosphorus are the main things needed at this stage. Phosphorus helps the plant roots to absorb nitrogen in an effective way. Potassium and calcium are the lesser required ingredients.
When a seed is sprouting, too much nitrogen may burn it. So the nitrogen should be minimal when watering the seed beds and should be increased gradually.
Flowering to Fruit – Teenage
When flowering, things change in the plant’s chemistry. Plants need to attract pollinators therefore it should have a good amount of sugar in the flowers. With the nitrogen and phosphorus feeding above, we need to read about 12 brix with a TDS refractometer. 12 brix is the breaking point between the simple and complex sugars. Also the plant is preparing itself for the fruiting. If the sugars are not enough in the sap, there will be bug pressure as the bugs usually attack low brix plants. Phosphorus being the most required along with medium application of calcium and potassium. Little amount of nitrogen should also be applied.
Apple, apricot, peach, cherry and pear trees burst into flowers before any leaf growth. So they need a different diet. I am getting good results by mixing liquid fish fertilizer and phosphorus worm castings and applying them to soil and leaves as liquid fertilizer.
Fruit to Ripening – Reproducing
When the fruits are visible, plant’s nutrient requirements are pretty much at its maximum. Plant is using all its energy to grow the fruits with viable seeds in them to guarantee its continuity. Soil needs to have a good balance of mycorrhiza and bacteria along with moisture. A mulch layer will be keeping the roots cool and temperature fluctuations between the day and night are minimum. The stem is strong and vigorously growing. Leaves are large and ready to utilize the sun’s rays. Calcium is the main ingredient here at this stage along with potassium and phosphorus in lesser amounts (than other stages). Nitrogen is still required in very little amounts, if the soil is healthy, the residual nitrogen should be enough.
When the fruits are ripening, there is strong bug pressure. As the plants are trying to guarantee their next generation, bugs are also trying to lay eggs on suitable plants for the next generation (or they already have). Leaves are eaten, fruits have already maggots in them, soil bugs are everywhere. If you want balance in your garden, you must have a bug hotel and various sizes of bird boxes scattered in and around your land so that natural predators are also around. You should prune the plant removing old, yellow leaves and new growth that is shading the fruit but if the leaves are close to fruit, leave them there. At this stage water requirements are not huge like other stages. Reduced water increases the concentration of sap sugars and bugs do not like eating too much sugar, as the sugar converts to alcohol in their body and they become lunch for birds while flying drunk. The plant needs greater levels of calcium and consistent levels of phosphorus and potassium, and calcium almost 1:1 ratio.
Dormancy – Winter Sleep
Once the fruits are harvested annual plants start dying and perennials try to grow a bit more if the weather permits. After the first strong frost, the hormones change in the plant and perennials go into dormancy stage. At this stage, unnecessary nutrients stored in leaves and dropped on the ground to become mulch. Roots are still functioning and looking for nutrients that might be used at next growing season. Mushrooms may fruit on the floor or start decomposing complex fibers and returning them to soil as nutrients. Bacteria is not as active as warm days but mushrooms are. Nature’s soil feeding starts at colder months. All those lost minerals should be returned back to the soil. Organic content should be replenished. The reserves that are empty should be filled. Potassium and phosphorus should be topped up. If we assume the roots of a fruit tree are as wide as the drip line of it, we should feed about 70-90cm out from there with our potassium and phosphorus worm castings so that roots can sniff this and start growing in that direction.
If there were leaf curl or other bacterial outbreaks before, you might want to wash branches with neem oil and worm juice mixture with the help of kelp and anti-bacterial solutions prepared around end of winter.
My main fertilizer production happens in two ways.
1- Fish fermentation buckets
Wild caught fish (fresh or salt water) anaerobically fermented using kefir and a bit of boiled potatoes. An air lock is situated on top to prevent oxygen. Resulting product diluted and sprayed on leaves and soil.
My fish fertilizer recipe is slightly different than the ones found on the web. I don’t use sugar or molasses. My starter culture is not wild collected LAB or yeast. I am also using boiled potatoes as starch so that bacteria and yeast have some food to thrive. Basically diced fish and water (preferably rain water) is mixed. Boiled mashed potatoes are added on top. Strained kefir (kefiran) added and stirred. An air lock is used to release the CO2 build up. This takes about 4 months to fully ferment. You will notice that not even the largest fish bones stay intact. Everything dissolves releasing nutrients. I also add some kelp if I have it on hand.
From a diversity perspective, kefir is superior to any wild collected effective micro-organisms and being acidic, a smaller amount of harmful bacteria is present. Inoculating the fish fertilizer with kefir makes sure the good bacteria are greater in numbers and they will out compete the bad guys. You need to find the real kefir gems (grains) though; the sachets of culture sold at health shops will not work as good as kefir itself.
Catch some carp and make your own fish fertilizer. This is the only nitrogen fertilizer you will need. This fish fertilizer will have a greater amount of diverse microbiology and minerals too.
I have 20L buckets which I fill up to half with diced fish and rest of the way with water or whey, leaving the top 10cm empty. I then place 2 large boiled and mashed potatoes, 500 ml of kefir and either fresh or powder kelp on top. The mixture is then stirred with a long stick making sure kefir distributes throughout the bucket. Next, close the lid and seal with duct tape. The lid has an air hose that is secured with silicone. This air hose goes into a bottle of water. The idea is CO2 will travel through this hose and will bubble up in the bottle, not letting in the oxygen.
Warning: Don’t use fish waste from a fish shop, especially salmon bones and head. Usually these salmon are farmed and one of the most toxic, antibiotic loaded food ever. Go and catch some carp, it will be fun… For foliar applications, I dilute 30ml to 20L water. I use 50ml to 20L water for soil drenching and mulch activation.
Apply the fish fertilizer:
a – Once a week during the “Seed to Flowering” stage,
b – Once every fortnight during the “Flowering to Fruit” stage and
c – Once a month during the “Fruit to Ripening” stage.
2- My worm farms
A careful feeding regime depending on above stages will give us the best worm casting.
If you are not feeding your worm farm specifically, you won’t get much out of it. For this reason we need to grow, make and collect some material. The term “black gold” will be restored to its glory with a bit of careful feeding of the worms. You will get much more healthy plants and juicy fruits with my methods.
All my kitchen scrap go into worm farms except citrus, onion peels, bones and fat. I make cheese most weekends and remaining whey is also fed to worm farms just to provide moisture and not as a run off so that nutrients are not leached. Soil, coffee grounds, comfrey, dandelion and common weeds and autumn leaves also go in if there is space.
If you just feed your worm farm with kitchen scrap, the end result will be just some black sludge without much of the nutrients. You only get what you put in. So make sure you are feeding the worms properly. The things I use are:
- Spent coffee grounds from café shops
- Grow comfrey. If you still don’t have comfrey in your garden, get it now.
- Fallen leaves in autumn. These are only collected from my yard.
- Grass clippings and yard scrap, dandelion, nettle.
- Cardboard and shredded paper.
- Soil from my garden.
You need 3 separate worm farms specifically fed a different diet each. Each worm farm gets equal amount of kitchen scrap, yard scrap and weeds. You can spray diluted fish fertilizer to keep moisture to 65-75%. Make sure they are covered to prevent rain getting into them and leaching the nutrients into the worm juice. If juice is collected underneath, use this to increase the moisture but don’t mix the juices i.e. don’t use phosphorus worm juice on potassium worm farm. Also keep the tap on the worm farms open all the time to provide air circulation.
Phosphorus Worm Farm
After boiling your bone broth separate the bones, add egg shells, crustaceans shells, sea shells and burn them in a chamber (with less oxygen). They will turn into charcoal and the higher the better the temperature is. Pulverize the bones with a hammer. Resulting dust should be fed to worms for further processing. This will give us the required phosphorus in our worm castings. Larger pieces that don’t go through worms will be home to beneficial bacteria. This worm farm should be slightly more acidic than the other two so needs to be watered with diluted fish fertilizer and a bit of AC vinegar for the phosphate to come out.
Potassium Worm Farm
Citrus peels charred in high temperature are a source of potassium and calcium but also provide other elements like manganese, iron, copper and zinc. I collect citrus peel outside during the winter as we eat a lot of oranges. Once I have a substantial amount of peels, I put them in a tin can which has holes around it and put the can in my meat smoker during a smoking session. While the meat is getting a nice citrus aroma, the peels charred and ready to use in my worm farm. We need to pulverize them as much as we can so that worms can eat them.
Calcium Worm Farm
Put dry egg shells in a blender and pulverize. I recommend getting a second hand blender for this purpose. Egg shells, once broken, are sharp and ruin the blender. Feed the resulting egg shell dust and comfrey leave to worms. Water well with diluted fish fertilizer.
Using the castings out of these 3 worm farms on soil by burying them into trenches is the best method but you can also prepare compost teas for foliar applications. An air source is required to provide oxygen during the tea extraction and to favor good bacteria. You can do a foliar application in the evening while the temperatures are below 14C as the stomata closes above this temp. Application would still be beneficial above 14C but do not apply under direct sun.
Note: A big thanks to Yvette Faraone for proof reading my article and correcting mistakes.