Top 5 Organic Fertilizers REVIEWED

, written by Benedict Vanheems gb flag

Granular organic fertilizer

Look on the shelves of any garden center and it’s easy to feel bewildered by the astonishing variety of fertilisers and soil amendments. But which are best, and when and how should you use them?

Organic vs Synthetic Fertilizers

There are two main types of fertilizer – organic and synthetic. So which is better? Well, on this channel we always recommend gardening organically. It’s easier (and cheaper!) because there are fewer artificial inputs, and it promotes long-term plant and garden health. We’re literally working with nature here!

I often compare organic feeds and fertilizers with unprocessed wholefoods. Wholefoods nourish a healthy body, keeping you well, trim and happier in yourself. On the other hand, synthetic fertilizers contain manmade ingredients that have a short-term effect on plants. They’re not all bad, but most of them can be thought of as junk food: they make you feel great (for a while anyhow), but quickly leave you depleted and craving more. Synthetic fertilizers, like junk food, won’t sustain the long-term wellbeing of your plants.

The word ‘organic’ means anything that comes from a living organism. That includes compost and manure, as well as any plant feeds derived from the remains of plants or animals. Once applied, these organic materials will gradually get incorporated into your garden’s ecosystem, becoming part and parcel of its natural cycle and contributing to its future fertility and ongoing functioning.

A compost heap is an essential part of any healthy garden

Organic Matter to Improve Soil and Enhance Fertility

Organic plant food begins with compost and manure. This is the ultimate plant food: a natural source of nutrients released slowly and steadily to your plants, while also improving the condition and structure of your soil over time.

Many successful gardeners nourish their plants on nothing but compost and well-rotted manures. That’s how nature does it, so it’s no surprise this works just as well in the garden.

Compost everything you can to make your own free fertilizer: throw in spent crops, kitchen scraps, old flowers, leaves, annual weeds – the lot. There’s no sense in putting it out for collection! Why do that when you can turn it all into a truly valuable resource to feed your crops?

Manure is a rich source of nutrients for your plants

You should only use well-rotted manure from herbivores – cows, sheep, horses, rabbits etc – and make sure that the animals haven’t fed on anything sprayed with persistent herbicides that could affect your crop.

Apply your compost or other manure to the soil at planting time or lay it around actively growing plants as a mulch to help feed them steadily, boosting your chances of a truly nutritious, bumper crop.

I also like to add it whenever I lift a finished crop, even if the ground’s going to remain bare for some time. The nutrients won’t wash away, and it will help to keep the soil and all the beneficial organisms in it happy until it is time to plant.

Organic fertilizer pellets are convenient and easy to use

Organic Fertilizers for Steady, Healthy Growth

Pelleted fertilizers, such as chicken manure pellets, are basically dried organic matter that’s been pressed into pellet form. Because there’s very little moisture left, manure pellets are more concentrated than farmyard manure, which makes them great for new plantings of particularly hungry crops like cabbages and other greens.

Other common pelleted products include comfrey pellets – again, nothing more than dried out and pressed comfrey. Comfrey is a great source of potassium and trace elements, making these pellets a convenient, clean, easy-to-handle way to boost flowering and fruiting plants such as squashes, tomatoes and peppers. Like bulkier organic matter, pellets will break down into the soil over time, contributing to its overall health and condition.

Organic fertilizers contribute to good soil structure as well as fertility

Bonemeal, Bloodmeal, and Blood, Fish and Bone

Organic granular fertilizers usually contain animal by-products, for instance bonemeal. Bonemeal is a fantastic fertilizer that’s high in phosphorus, which encourages good, strong roots. It’s just the ticket for helping establish newly planted trees and shrubs, as well as promoting excellent growth in root crops like carrots and parsnips. As the name suggests, this is nothing more than the ground-up, dried bones of animals.

Another byproduct of the animal industry in bloodmeal, or dried blood. It’s a fast-acting fertilizer that is especially high in nitrogen, making it ideal as a top dressing around leafy plants like lettuce, chard, or brassicas like kale. It’s also great for kickstarting decomposition in straw bales for anyone looking to start a straw bale garden. Hoof and horn is another granular fertilizer that’s high in nitrogen.

Finally there’s fish, blood and bone which, no prizes for guessing, contains dried blood and bone as above, with the addition of fishmeal. The result is an almost perfectly balanced fertilizer with nitrogen from the blood, phosphorous from the bonemeal and, with the addition of the fishmeal, potassium for flowers and fruits. This makes it a great all-purpose feed for use all around the vegetable garden, and in the garden generally – sprinkled and raked into the soil before planting, or as a top dressing around actively growing plants.

Calcified seaweed improves soil and encourages healthier crops

Condition Soil with Calcified Seaweed

One of the very best soil conditioners you’ll find is calcified seaweed. The calcium helps to break down heavy clay soils, while the seaweed is a boon to beneficial micro-organisms in the soil. The result? Better soil structure and a thriving soil ecosystem that encourages strong roots and healthier, more vigorous plants.

This totally organic granular fertilizer is a real all-purpose powerhouse. Use it to green up lawns early on in spring, as an alternative to lime for your brassicas, or to boost your crops, triggering more flowers and fruits. Do make sure that the product you buy has been harvested sustainably though.

Organic liquid feeds get to work quickly to nourish your plants

Fast-acting Organic Liquid Feeds

Liquid seaweed concentrate also contains the riches of the sea – seaweed really is magic stuff! It’s fantastic for fruiting crops like tomatoes. You can also use homemade comfrey or nettle teas.

The real strength of organic liquid feeds is that they are absorbed along with the water that carries them mere moments after applying. This makes them very fast acting! In the case of liquid seaweed, you’re adding a fantastic rainbow of trace minerals too. It works really well for giving plants a boost when used every few weeks. Just make sure it says organic on the label, or you may also be inadvertently adding artificial additives.

Organic fertilizers and feeds can make a huge difference to your garden, giving it a boost not just right now, but in the longer term too.

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"Hi what breed dog does this British guy have? The doggie is so cute! thank you"
Gwen Parrish on Friday 1 April 2022
"It's a cavapoo. :-)"
Ben Vanheems on Monday 4 April 2022

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