Garden School:


Garden School:
Teaching this week: Planning a project, and how to do Quantity Surveying, in order to establish the quantities required.

Monday, 5 October 2020

Organic Fertilisers: How to Make Your Own

Many gardeners are now trying to reduce the amount of commercially-produced chemicals which we are liberally spreading all over our gardens - this is a good thing to do, for many reasons: and one quick and easy way to get started is to make your own organic fertilisers.

There are many recipes, but two of the easiest are Comfrey, and Nettles.  Not together! Separately.

You may already know that Comfrey - left - contains a lot of protein (25% by weight when dried, apparently) which is why it has been used as fodder in the past, and is still fed to chickens today. 

The proper name is Symphytum officinale, and if you are ever using plants for any purpose other than just looking at them, then it's vitally important to get the correct plant, so learning the proper name is a good first step.

As an illustration of that point, one of the UK foraging sites warns: 

 "Comfrey contains pyrrolizidine alkaloids some of which can harm the liver so some foragers no longer consider this a safe plant to eat... White flowered Comfrey does not contain echimidine, the pyrrolizine alkaloid that is causing concern at the moment so wait until the plant flowers and eat only from the white flowering variety."

This is absolutely true: on 2008 the FDA (Food and Drug Administration, US) banned the sale of dietary supplements which contain comfrey, and they specified Symphytum officionale (common comfrey), S. asperum (prickly comfrey), and S. x uplandicum (Russian comfrey) .  

 Interestingly, when this was reported on a medical site in the US, they said  "Scientific and common names: Symphytum officinale, Symphytum radix, Consolidae radix, comfrey, Russian comfrey, ass ear, black root, gum plant, healing herb, knitback, salsify, slippery root, wallwort, knitbone, bruisewort, blackwort "  which is a rather scary insight into why we have to learn the proper names of  plants, if we want to use them medicinally. All those common names! 

In the UK, Salsify is a completely different plant! 

It's proper name is Tragopogon porrifolius and the roots are allegedly edible, although apparently not very nice. Waitrose did try to introduce them as an unusual vegetable a couple of years ago, but gave up.

This - left - is the beautiful and ornate seed head of Salsify, looking like a cross between a jellyfish, and a dandelion on steroids.

Anyway, back to Comfrey: "eat only white flowered Comfrey" they said: White Comfrey is Symphytum orientale: but there is also Symphytum grandiflorum, which is also grown in many gardens, and this one has creamy white flowers. Would you be sure that the flowers were white, or were they creamy white?

 Now you can see why I always encourage people to learn the proper names of plants!

Common Comfrey, though - S. officinale -  is grown on many allotments, so it's very easy to get hold of.

Talking of "easy to get hold of", the other useful fertiliser plant is common or garden Stinging Nettle: I will remind you of the proper name, Urtica dioica, but you don't need a photo, because everyone knows what stinging nettles look like! As is always the way with botany, there are several other plants which you might confuse with nettles, but it's an easy one to find: if it stings you, it's stinging nettle.

I'm sure you've all read that “nettle tea is a delicious and beneficial beverage” - although I have to say, I've never tried it myself, nor do I particularly want to... and it makes you wonder just how desperate people were, to start trying out ways to make tea from nettles.  An infusion of nettles in water has been drunk, time out of mind, long before the World Wars: but it was only during the rationing of WW2 that it was called "nettle tea", in an attempt, I think,  to make it sound more like "tea", and therefore to encourage the the populace give it a go.

But both of these common weeds can be put to use in the garden: they contain a lot of nutrients, as they both have deep root systems which can extract minerals from the soil, at depths that many other plants cannot reach.

This year, why not have a go at making your own organic plant food from Comfrey and nettles? By watering -  or spraying -  your plants with an extract made from either or both of these weeds you can provide nitrogen, and lots of yummy trace minerals.And although it might feel a bit late in the year to do it, well, now is a good time to practice, and get the hang of it, then next year you can swing into full production.

These feeds are not a substitute for good soil care, of course, but can be very beneficial for plants growing in confined spaces such as pots or containers: and it provides a top up of nutrients in a readily available form that plants can use quickly - and best of all, it's free! And organic!

It's very easy: put on some gloves, get a bucket, and fill it with either chopped comfrey leaves, or with chopped nettles. Ram them down well, then add just enough water to cover them. Put a lid on the bucket, and leave it - two weeks for nettles, six weeks for Comfrey. Stir, or poke it with a stick, every now and again, and prepare to hold your nose as you do so, as it's quite stinky!

After the requisite time, strain off the disgusting smelling, dark brown liquid, and dilute it 1:10, ie one cupful of brown liquid to ten cupfuls of water. You don't have to be too precise about the dilution, as long as you end up with liquid that looks a bit like weak tea. This can then be sprayed onto the foliage, or watered in around the base of the plants.

Is that it? Yes, it really is that easy! If you don't have either of them growing in your own garden (stop looking so smug, we can see you!) then pop down to your local allotment and ask if you can collect a bagful.

To make it even easier, you can stuff the chopped leaves into hessian or muslin bags (or some old tights) before soaking them, so you don't have to strain them: and yes, the leftover mush can go straight onto the compost heap.

So why not give it a go? And best of all, you have a perfect excuse for not brewing that delicious and nutritious cup of Nettle Tea: “Sorry, I've used it all for the plants!” 

 

 

Did you enjoy this article? Did you find it useful? Would you like me to answer your own, personal, gardening question? Become a Patron - just click here - and support me! Or use the Donate button for a one-off donation. If just 10% of my visitors gave me a pound a month, I'd be able to spend a lot more time answering all the questions!!

No comments:

Post a comment

Please note that I do not allow any comments containing links: any such comments will be removed immediately!