Everything in the food chain needs to eat. From humans all the way down to beneficial bacteria; we all eat. A few species along the way are mostly carnivores, a few are herbivores, but the majority are omnivores, including the soil and the many of the microbes that live in that soil. For the sake of time and the focus of this article, though, we’re going to stick to discussing our soil and the nutrients our fruit and veggies need to grow and thrive.
Many gardeners think of the earth as merely a growing medium, something to hold plants while they grow, but it’s so much for than that. Think of the earth as either growing or dying. The way we treat the soil, whether in beds or containers, will either develop and grow the soil or it will kill it.
The soil is the receptacle that houses the nutrients that grow our plants. Water is the vehicle that transports the nutrients TO the plants, as they are on a liquid diet, so to speak.
Plants require several nutrients; primarily Nitrogen, Phosphorus, and Potassium, (NPK). Most commercial garden fertilizers advertise their NPK ratios right on the bag or box. As an example, you might see 5-5-5 or 4-1-1, etc. In the first case, it means 5 parts Nitrogen, 5 parts, Phosphorus, and 5 Potassium. The second example is 4 parts N, and one part each of P and K.
Each variety of fruit and veg you grow has its own requirements, so one size doesn’t always fit all. A good, healthy nutrient rich soil will go a long way to meeting most plants needs and your fertilizer will mostly supplement what’s there. Before we go, I’m going to show you a great workaround in choosing your fertilizer. But first I want to show you how to minimize your requirements for them.
If NPK was all plants needed, things would be pretty simple, but the truth is, plants need much more. NPK are called Macronutrients, while the lesser requirements are called micronutrients. However, there are some others I consider Macronutrients, because they make a huge difference in performance.
The first is Magnesium. Magnesium is to plants what Vitamin B complex is to humans. It boosts energy and vitality. The easiest way to get Magnesium to your garden is via Epsom salts, which by the way, are not salts at all. While I add some to my garden beds, most of the time, I add the Epsom salts to my regular watering regime. It is easily dissolved and is very easy for plants to take absorb it through their leaves, or to take it up via their roots.
Secondly, plants need Calcium, especially varieties that produce fruit like tomatoes, peppers, squash, cucumbers, etc. There are some great water soluble Calcium products, but it’s really easy to add garden lime, egg shells, oyster shell or something similar to the soil at the beginning of the garden season when you’re working your beds.
Third is iron. We don’t think of it enough. There are many great natural products on the market to enrich the iron content of your soil. Remember, the general principle is, we feed the soil so the soil can feed the plants. Are we making sense so far?
Oh, something that happens more frequently that we realize is what’s called, nutrient lockout. The short version is, there are nutrients in the soil, but the plants can’t access them. This is where beneficial bacteria (microbes) come in. One of the best supplements you can use if you have a particularly bad patch, would be humates. Humates, mostly humic acid help bind the carbon to the nutrients so your plants can take advantage of those nutrients. Humates are available in bag form and in liquid concentrate. In bag form it’s added directly to the bed and worked into the soil. In liquid form, it’s diluted and added either directly to the soil, or used as a foiliar spray.
Many studies have shown that humates improve nutrient uptake by 30% to 50%. That’s huge. In an future update, I will focus on the benefits and types of humates, but for now, let’s get the principles.
There are many types of soil amendments available to build soil; straw, wood chips, perlite, leaves, all come to mind right away. If you’re going to use wood chips or straw, I encourage adding them the autumn before you plan to plant to give them time to better decay. Perlite and leaves can be added when you begin to work up your beds. I’ll explain about the wood chips in a future update.
Obviously, good rotted horse, cow, or chicken manure is awesome. But make sure it is well rotted. The best ways to do that are to make a compost pile and let nature take its course, or to add some compost worms to the edges of the pile after it’s been standing a few weeks. A third way, and maybe the best, is to let chickens have access to your compost pile.
Better than any of those other manures is rabbit manure. Rabbit manure is not ‘hot’ like what comes from more traditional livestock. In simple terms, the nitrogen and ammonia in most manures is so rich and dense that it can burn the roots of plants. Rabbit manure is ‘cold’, as if it’s already been composted. Goat manure is great, too, but they aren’t usually confined like rabbits, so it’s harder to get it raked up and used. Goat manure from a stall or paddock is usually full of straw or wood chips, and needs a great deal of composting.
If you have a pet rabbit, you’re already in luck. If you don’t maybe it’s time to consider it. J. A pair of bunnies will provide hours of enjoyment, loads of baby cuteness, tons of fertilizer, and for true omnivores, many pounds of the healthiest meat on the planet. I know that here in the USA, we think of rabbits as either pests or pets, but with the possible exception of goat meat, rabbit is the most consumed meat in the world. Ask any heart specialist about the value of rabbit meat. (Note: we’re not going to debate eating rabbits. This is an omnivore site and I’m an omnivore. If you don’t want to eat rabbit, no worries, don’t. Just enjoy them as pets and as little fluffy manure factories.)
The great thing about rabbit manure is that you can apply it directly to the garden without composting. Talk about convenience. In the early days, I would just empty the trays below the cages into a wheelbarrow and take it straight to the garden beds. These days, I prefer to put it in my worm compost bins. The worms compost the rabbit poo fairly quickly and the compost is even better than the straight rabbit manure.
So, worm composted rabbit manure is my number one choice for the garden. Straight rabbit manure is my second choice, and worm castings are number 3.
In a future episode, I’ll give you a secret recipe for the perfect compost mix, but this is the fertilizer issue, so I’m going to share two very similar fertilizers that in my experience are the best options for new and intermediate gardeners.
The first is Sea Grow 16-16-16.
This is a water soluble, seaweed based formula that is perfectly balanced and contains micronutrients. The only thing you need to add is calcium and magnesium. It is ideal for raised beds and containers. If you have a good soil mix to begin with, you can dilute the Sea Grow to a 50% strength with some calcium/Magnesium and you’ll have great results. I mostly use a hose end sprayer, but in the greenhouse, when I’m feeding, I will mix the sea grow in a watering can.
My second recommendation is very similar to Sea Grow and is called MaxSea 16-16-16. Instructions are the same.
I also use both products in small Deep Water Culture Hydroponics systems for growing lettuce and greens. IMO, the Sea Grow gets better results in hydroponics systems, but there is no difference between them when I use them in soil.
There are other formulas in both products that are designed for different growth stages. Frankly, in soil and container gardens, I haven’t seen the benefits of the ‘bloom’ formulas. If you’re going to grow blooming and fruiting plants hydroponically, then adding the bloom formula to the mix once buds appear, can improve results. But we’ll save that for another day.
If you don’t want to deal with mixing water soluble formulas, then consider the Jobe’s line of products or the line from Espoma. Both are available from most garden centers and big box stores. In the long run, I believe the Sea Grow and Max Sea are more versatile and less expensive, but I’ve gotten great results with Jobe’s and Espoma.
There is an enormous array of fertilizer options on the market. Please do some homework before you just go buy something that promises miracles; especially if you want to use products that are good for the soil.
That’s it for this week. If you try, or have tried, my recommended fertilizers, let me know how it goes. I’d also love to hear your recommendations.
As mentioned earlier, when we get closer to Spring, I’ll give you my recipe for a dynamite soil mix. Talk to you soon.