How To See If A Plant Is Edible or Not – The Universal Edibility Test



How to see if a plant is edible or not? The Universal Edibility Test is technique through which people can safely test various plants in the wilderness and see if they are good to eat. In the event that someone is lost in the woods or on a deserted island or wherever, this test can literally save their life.

Eating wild plants is not indicated as it is more likely that looking for them will make you burn more energy than they give back. There are also many plants out there that can outright kill you if ingested or at the very least, make you violently ill. This is why, eating wild plants should always be taken as a last resort, and in the face of severe starvation. The best way to survive such an extreme situation is to prevent it from ever happening in the first place and no extra precaution, when hiking and living in the wilderness, is overkill.

Now, let’s get started with the universal edibility test. First thing first; the test takes up to 16 hours so you should be prepared for this and don’t skip on any of the steps; no matter how hungry you are.

Step 1 – Looking for an abundant plant


The first thing you need to do is to look for a plant which is abundant in your vicinity. Like we said before, these wild plants are very likely to offer you very little nutrients and it would be extremely wise to pick something which is in abundance in your immediate area.

Step 2 – Avoid umbrella shaped white flowers

Hemlock flowers - Universal Edibility Test
Hemlock flowers – How to see if a plant is edible

Poison hemlock and water hemlock are two, very common and extremely poisonous plants found in the United States and Europe. Water hemlock is smaller and lives by the water, while poison hemlock is taller (sometimes even 6 ft. <->2 meters tall). Nevertheless, both have a small white flowers that clump up to make an umbrella shape – just like the image above. Stay away from these plants as they will kill you!

If the season is not right for them to have flowers, you can pull the plant out of the ground and see if the root looks and smells like a carrot. If it does; stay away from it because that’s hemlock.  

Step 3 – Avoid waxy leaves, thorns or hairs


Avoid plants whose leaves are waxy; just like the holly tree. Avoid those plants as they are most likely poisonous. Also watch out for plants which have thorns or hairs anywhere on their bodies. With the exception of the nettle (which is edible), most plants with hairs are poisonous. Even the nettle should be eaten when the plant is young and first appears in spring.

Step 4 – Look at its sap


Almost all plants that are poisonous out there have a white, milky sap. To see this for yourself, you just take some leaves, you break them open and squeeze out the sap. If it’s white; keep on looking, if not and the sap is clear (and if the plant complies with all steps above), the plant MIGHT be safe to eat.

Step 5 – The skin test


This is actually the first step in the universal edibility test. The others up until now can save you precious hours of looking and will narrow your search significantly. Now, how to see if a plant is edible or not?  First thing you need to know is that you should always test only one part of the plant (eg. only its leaves, stem or roots) as some plants may have one of these parts edible while the rest poisonous.

You take that part of the plant, you brake it open and then you rub it on a small part of your skin (eg. your forearm). You wait for about 20 minutes and look for any kind of reaction (eg. swelling, burning, reddening, itchiness, numbness, anything). If this is the case, the plant failed the test and you need to look for another one.

Step 6 – The mouth test


If the plant passed the previous test then you should take a very small piece of it and set it in your mouth, just under your tongue and try not to swallow any of your saliva during this time. Leave it there for another good 20 minutes or so. And again, look for any type of sensations like before. If something is out of the ordinary… you know the procedure; throw it away.

Step 7 – Just a taste


If nothing happens, you take about a spoon-full of the plant and swallow it. Again, you wait for any type of reactions (diarrhea, stomach cramps, vomiting, pains; anything out of the ordinary). If something like that happens; stay away from that plant. If not, and 8 hours have passed, you take a cup-full and repeat the procedure (again for 8 hours). If nothing happens again, it’s possible the plant is safe to eat. 


This is pretty much the universal edibility test and this is how you see if a plant is edible or not. But you have to keep in mind that you won’t get much nutrition out of them. They will most likely still give you diarrhea because your body isn’t used to eating those types of plants. If this happens you can risk dehydration. Poison can still be found in the plant but in trace amounts. If you eat too much of it, the poison could build up in your system, so be careful.