Feeding the soil so it can feed us
I was reading about ancient traditions that celebrated the cross quarter days- the time half way between solstice and equinox. February is often seen as the time when the earth is beginning to awaken and the light is coming back. I loved a tradition from Ireland that buried a loaf of bread symbolically feeding the earth in hopes of a good harvest. Where we live, the soil is not covered with a layer of snow so it is a good time to literally think about feeding the soil. The soil cannot give you food if you do not feed it.
It is worth having a plan and some actual knowledge behind what you feed your soil. I recommend anyone having problems with their garden or if your garden is big to get a soil test. It will tell you what you are missing and what you have in abundance. This is not one of those home tests that vary in accuracy, take it in to Harmony Farm Supply or another location that sends the soil to a lab for a thorough test. Small gardens where everything is growing fine are not probably worth getting tested.
The first time I got a soil test for a large garden I was tending it came with a great booklet on how to amend the soil based on the results of the test. Not surprisingly under every single area the first thing recommended was “add compost”. No matter what the problem, compost is recommended. It adds nutrients but it also adds humus (organic matter) which holds the nutrients in the soil and microbial life that make nutrients in the soil more readily available for plants to take up. I recommend 2-3 inches of good compost on a garden bed on a yearly basis. If you are planting high feeders, you can add it when you replant so it might be twice in a year. More compost is not recommended by anyone I have ever talked to.
Besides compost I recommend adding amendments for balanced, healthy growth. Amendments or fertilizers are added as needed depending on your soil or if you have not done a soil test I recommend adding a fertilizer that is made for vegetables and has a mix of ingredients.
Nitrogen is one of the main nutrients needed for plant growth. It is the N in the N-P-K listed on all fertilizers. Nitrogen is responsible for plants’ green foliage. Plants that are mostly green leaf need more nitrogen then plants that are fruiting or flowering. Nitrogen is most important in the early stages of growth. The main sources of nitrogen fertilizer are Blood Meal, Fish Meal, Cottonseed Meal, Feather Meal, manures and legume cover crops.
Phosphorus is the P in NPK, and it is the main element needed for healthy flowering, fruiting and rooting. It is found mostly in bones or very old bones and is often bound with calcium in its chemical form. It is slow to release and needs high microbial life to make it available to plants. It does not need to be added as often as other nutrients as it lasts several years in the soil. Soft rock phosphate and bonemeal are both good sources of phosphorus but can only be accessed in acid soil. If your soil is alkaline then you need to add something like Bat or Seabird Guano which is also high in phosphorus.
Potassium is the K in the NPK and is crucial for the plants vigor and health. It helps regulate growth. Potash or potassium is available in most organic matter so compost is a good source for it. Wood ash is also a source but is extremely high and can burn your plants and roots so should only be used in small quantities. Two main sources of potassium are green sand (from ocean deposits) and sulfate of potash. Potassium can leach out quickly if your soil does not have enough organic matter so in poor soil it should be added yearly.
Trace Minerals are also an essential part of soil and plant health. Focusing on only the NPK can lead to problems if you are not also paying attention to the trace elements. They are critical for plant health just not in as large of quantities. The key ones are calcium, magnesium, sulfur, and sodium along with the micronutrients of zinc, manganese, copper, iron and boron. Kelp is rich in minerals so kelp meal or a liquid kelp is a good addition to the soil. Calcium is important in building cell walls, many calcium amendments affect the ph of the soil, what you use is dependent on the ph of your soil. I can’t go into all these but it is important to make sure you are also feeding these to your soil. Maybe a future blog can go into the micro nutrients.
If you still don’t know where to begin on feeding your soil, I recommend these things: compost, a basic fertilizer mix for vegetables and if that mix does not carry kelp then kelp meal or liquid seaweed when planting. Once again if you are having problems with vigor or health in your garden, I highly recommend a soil test.