Nettles: When to stop picking?

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Ash Blue

Tenderfoot
Jan 19, 2007
99
0
34
Manchester
Different books give different ideas on when to stop picking and eating stinging nettles. I would like to fill a freezer but I think it might be too late now. I hear about the fibers that can be harmful if picked too late. Just looking for confirmation on the latest time to forage nettles?

I'm also wondering if nettles would be fine any time of the year if made into a tea? I'm just assuming this because it won't contain these tough fibers.
 

Bartooon

Nomad
Aug 1, 2007
265
0
68
New Forest
As soon as the flowers start developing, you should stop picking nettles for consumption. Once they reach this stage they are microscopic rods of calcium carbonate, known as cystoliths. These are absorbed by the body and can cause kidney problems. I would probably avoid tea too at that time.

If you chop a clump back they will produce a secondary growth with young, tender edible leaves that you can carry on using.
 

Toddy

Mod
Mod
Jan 21, 2005
38,998
4,650
S. Lanarkshire
It's not the fibres that's the problem; it's the crystals that develop as they age.

Basically, if they're more than knee height they're not so good to eat. You really want shoots about a handspan long. By now they're growing fibres to supply the height and the seed heads with water, so no, not very good to eat, though it's the leafy and soft new shoots that are eaten rather than the hard stems.

What you can do though is chop them down to the ground and they'll sprout again with fresh new growth. That growth, if you get it quickly enough, they toughen up fast with the longer and stronger sunlight, is edible.

The crystals are bad news for your innards, but they're usually a late summer and autumn problem; basically avoid if at all possible.

Just now you can pick the leaves and shoots for tea, but not if they're in flower.

cheers,
Toddy
 

Ash Blue

Tenderfoot
Jan 19, 2007
99
0
34
Manchester
Thanks, you guys always give useful tips ;)

I have a huge patch about 1/8th of a mile away from footpaths. Is there a good method for cutting back the nettles for regrowth?
 

treadlightly

Full Member
Jan 29, 2007
2,692
3
65
Powys
Does this apply to the tips of nettles at this time of year, that is where there are new young leaves and no fibrous stem? Is this not similar to new growth out of cut back plants?
 

Ash Blue

Tenderfoot
Jan 19, 2007
99
0
34
Manchester
I've cut back about a 20ft area of nettles. What times of the year will this work and how slow does the growth get as it gets colder?
 

xylaria

Bushcrafter (boy, I've got a lot to say!)
I just eat the soft top leaves up until mid september(ish). I also eat the flowers stripped from the stringy stalk, and the seeds dried washed and fried. The seeds have noticable effect on the stimulating the bladder, but they are very nutrious and good eating, in smallish amounts with other seeds. I find my tongue tells me if something has too much fibre, if it is like eating grass it should be eaten by a cow not a human. I do eat things moderatly, nettle soup is more potato then nettle, nettle pakora has a cup full of finely chopped nettle tops go to 20 pakora. Nettles are a strong food, spinach they aint.

Edit ooohhh Here we go I havent heard of half the plants and I have never thought of eating begonias http://www.eattheweeds.com/bet-your-life-on-it-myth-busting/
 
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Danny1962

Member
Nov 12, 2014
19
0
Maidstone, Kent
The internet has many references to nettle leaves developing cystoliths as the plant matures. I'm sure this much is true.

The internet also has many references to these cystoliths causing urinary tract and kidney irritation. However I have not found any explanation for how this actually occurs. How does a cystolith, once consumed, find its way to the kidneys and beyond and cause the alleged irritation?

Has this actually happened to anyone on this forum, or anyone you know? Are there any medical case histories of this? If there are none, how do we know that these allegations are actually true? It could be just a myth that has ended up being continually circulated around the internet and which then gets accepted as fact.

It is probably reasonable to state that nettles are not so pleasant to eat once they have flowered, but I'm less convinced about the potential for irritation of the kidneys etc. Unless, of course, you know different!
 

Robson Valley

Full Member
Nov 24, 2014
9,959
2,666
McBride, BC
I'll make a botanical/biochemical guess:
The cystolith primary mineral content is calcium carbonate. I suppose that the calcium carbonate dissolves, come apart, in the ordinary digestive process.
These excess calcium ions can re-precipitate in urine (bladder stones) or in the formation of the urine concentrate (kidney stones).

Stony calculus formations in bladder and kidney are often associated with genetic predisposition. Nobody know what most of these
predispositions are but they seem to "run in families."

I wonder how much nettle had to be consumed in order to make the diagnostic connection? Three meals a day for a decade?
 

Toddy

Mod
Mod
Jan 21, 2005
38,998
4,650
S. Lanarkshire
Ah, I understood that the older leaves were high in calcium oxalate.

There's a load of mince talked on the web, there really is.

Calcium oxalate is poisonous….for a given value of poisonous (how much ? :dunno:) but some sites are recommending ingesting the older leaves to help dissolve kidney stones ! yet the stuff forms kidney stones ….

I'm hoping that one of the Medical Herbalists chimes in on the thread (Sandsnakes, et al ) because I'm confused trying to find out if I were right about the calcium oxalate or not, heaven help anyone trying to make sense of things.

M

p.s. link on wiki to calcium oxalate.
https://en.wikipedia.org/wiki/Calcium_oxalate

and a really good link on the herbal use (and it's medical trials) of nettles.

http://cms.herbalgram.org/expandedE...22&signature=aabf80a08916b9a0abab466c0e2f1b6a
 
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Janne

Sent off - Not allowed to play
Feb 10, 2016
12,330
2,294
Grand Cayman, Norway, Sweden
As you are not going to eat them at every meal for the next eternity, I would not worry.
I would not like to eat them if they grew on a brown site, land fill or beside a road though.

Prepare like spinach, also nice dried as an herbal infusion.
 

Danny1962

Member
Nov 12, 2014
19
0
Maidstone, Kent
Those crystals could well be the chalky cystoliths.

Chalk is commonly used in pharmaceuticals, both as a medicine in itself and also as a binder/filler for pills. It's also used as a food additive (E170). Nobody has ever suggested that it is harmful when consumed in moderation under these circumstances, so why would it suddenly become harmful when it occurs naturally in old nettle leaves? They wouldn't be very pleasant to eat, but I'm less convinced that it's actually bad for you.

Bladder stones could be caused by many things. Let's not blame the poor nettle!

Green Deane of Eat The Weeds is similarly sceptical (see Myth #3) http://www.eattheweeds.com/bet-your-life-on-it-myth-busting/

Janne, I have my "own" greenfield nettle patch and it's not near where people walk their dogs...
 

Robson Valley

Full Member
Nov 24, 2014
9,959
2,666
McBride, BC
Please be absolutley clear. Calcium carbonate is NOT calcium oxalate.
Why the Hello bother? Is there nothing else to eat in your environment?
If not, then read a little about a guy named Johnny Appleseed.
What stops you?
Oh, gosh, gee whiz. I'm promoting habitat enhancement. Illegal in many places.
 

Robson Valley

Full Member
Nov 24, 2014
9,959
2,666
McBride, BC
Transplanting things is the first step in the artificial selection of plant/crop breeds = here are 5 plants, which 2 will we dig up to plant near our cave?
I've done that with wild berry bushes for a very long time. Paleo kitchen gardens are still in use on Haida Gwaii.
 

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