Oxalis tuberosa (oca)

My girlfriend and I have kind of a thing for perennial vegetables, and in particular Andean root crops, many of which seem to grow especially well in our mild-winter, cool-summer Mediterranean climate. Oca is one of these, and it’s said to be second only to the potato as a staple root crop of the central Andes.

Home-grown oca straight out of the dirt
Home-grown oca straight out of the dirt

About a year ago we bought two oca “starts” while shopping for plants. It’s kind of silly to sell oca “starts” like that because they’re just oca tubers stuck in some dirt, with no roots or leaves growing yet, but I suppose the dirt does protect the tubers from light and drying out. Of the two, one died (probably from neglect and lack of water), but the other one made a nice sized oca plant and when we dug it up recently there was a decent crop of oca tubers. We saved the little ones for propagation and boiled up the big ones to see how they tasted.

Taxonomy

Oca is in the wood-sorrel genus Oxalis, in a family with not too many well-known edible members (starfruit/carambola is one). It’s also in the same genus as Cape oxalis which is a horribly invasive weed around these parts. The plants (oca and Cape oxalis) look very similar to each other and oca was probably cultivated from a wild ancestor similar to Cape oxalis.

Source

Straight out of our garden in front of our apartment.

Method of Preparation

Since we’d never tried oca before we wanted to keep it very simple and taste the intrinsic flavor. So I just boiled them for 20 minutes and ground a little salt on them.

Review

Same oca with most of the dirt washed off
Same oca with most of the dirt washed off

Tasted pretty much like boiled potato with a subtle sour taste. I read a description somewhere that said oca tastes like a baked potato with the sour cream already added, and I must say that’s spot-on. The texture is nice, more like a waxy potato than a big starchy potato. As with any starchy tuber, it’s pretty boring when boiled and eaten plain, but there’s so much potential here. Oca fries, oca hash browns, scalloped oca…

87 things I’ve already eaten (and you probably have too)

Welp, I said I was going to try to update almost every day, and here we are over a month later! In my defense, I did go through a major life change and have a completely new job now (I went from “physics PhD student” to “software engineer at an S&P 500 company”). But that’s no excuse – it should be this short, easy, and unstressful thing to eat something new and fire off a quick blog post.

To make up for lost time, here’s not one, but 87 plant foods I’ve eaten already, and that I don’t feel the need to post about individually because almost everyone in my part of the world has eaten them too.

I’ll only do this once – even if I think of something later like “D’oh! I should have put that on the big list; everyone’s eaten that!” I’ll still make a complete post about it.

Staple foods:

  • Corn
  • Oat
  • Rice
  • Soybean (also a legume)
  • Sugar cane (as sugar)
  • Wheat

Citrus:

  • Grapefruit
  • Lemon
  • Lime
  • Mandarin
  • Orange

Stone fruits:

  • Apricot
  • Cherry
  • Nectarine
  • Peach
  • Plum

Other culinary fruits:

  • Apple
  • Banana (fruit, not flowerbud or other parts)
  • Blackberry
  • Blueberry
  • Cantaloupe
  • Cranberry
  • Grape
  • Honeydew melon
  • Pear
  • Pineapple
  • Raspberry
  • Strawberry
  • Watermelon

Vegetables that are the fruit of a plant:

  • Avocado
  • Bell pepper
  • Cucumber
  • Green bean
  • Summer squash
  • Tomato
  • Winter squash

Leaf vegetables:

  • Cabbage
  • Kale
  • Lettuce
  • Spinach

Bulb, inflorescence, or stem vegetables:

  • Asparagus
  • Broccoli
  • Brussels sprout
  • Cauliflower
  • Celery
  • Onion

Root vegetables:

  • Beet
  • Carrot
  • Potato
  • Radish
  • Sweet potato

Legumes:

  • Black bean
  • Chickpea
  • Kidney bean
  • Lentil
  • Lima bean
  • Pea
  • Peanut (also a culinary nut)
  • Pinto bean
  • Soybean (also a staple)

Culinary nuts:

  • Almond
  • Cashew
  • Peanut (also a legume)
  • Walnut

Oil crops:

  • Coconut
  • Olive
  • Palm oil
  • Rapeseed
  • Safflower
  • Sesame
  • Sunflower

Herbs:

  • Basil
  • Dill
  • Oregano
  • Parsley
  • Rosemary
  • Sage
  • Thyme

Spices:

  • Black pepper
  • Chili pepper
  • Garlic
  • Ginger
  • Mustard seed (or as prepared mustard)
  • Peppermint (oil)
  • Vanilla (extract)

Drug-like foods:

  • Barley (as beer)
  • Cocoa
  • Coffee
  • Tea

And that’s about it! There’s a bunch of plants I’ve already eaten that aren’t on here, because I think they’re interesting/uncommon enough to merit their own posts. But this gets a lot of really common stuff out of the way.

Matricaria chamomilla (chamomile)

I want to update this blog fairly regularly (a good goal is “almost every day”), which means a quick post is better than no post. Today I drank chamomile.

Taxonomy

There are actually two species, in different genera, commonly used as “chamomile”. The more common is “German” or “wild” chamomile, Matricaria chamomilla, while “Roman” or “English” chamomile, Chamaemelum nobile, is also used. The dried tea had some whole flower heads still in it, and when I split one open it seemed like the receptacle was hollow rather than solid, so I’m pretty sure (though not 100% certain) that this is M. chamomilla.

Both forms are in the large family Asteraceae, which contains many edible crops including lettuce, sunflower, and artichoke. Within Asteraceae, they’re both in the subfamily Anthemideae, which also contains chrysanthemum and wormwood.

Source

Sara had a bag of dried chamomile purchased quite a while ago. The bag says “In Harmony Herbs & Spices”. Since it was a sealed ziploc, there was still a strong apple-like smell of chamomile when I opened it.

Method of Preparation

Sara is feeling like she has a cold so I just steeped some in boiling hot water for a few minutes. Maybe there’s some drug in it that actually helps, maybe not, but either way it’s a pleasant tasting hot drink.

Review

Chamomile has a slight bitterness (not as bitter as coffee or tea in my opinion), and a delicious apple-like scent. It’s not juicy or acidic like apples, but it reminds you of how apple skin smells, or dried apple bits. Overall it makes a fine tisane.

Momordica charantia (bitter melon)

Raw Chinese-style fruits
Raw Chinese-style fruits

It’s time for the first actual plant post! Today I ate “bitter melon” (Momordica charantia). This is a cucumber- or squash-like fruit which is extremely bitter (it ain’t called bitter melon because it’s sweet!), and is usually either sliced and cooked, or stuffed and cooked whole.

There are two kinds of cultivars of bitter melon: the relatively smooth Chinese style with rounded ends, and the Indian kind which has a much gnarlier surface texture, with pointed ends, and is usually a darker green.

I’d only ever heard of the fruit being eaten, but according to Wikipedia, “the young shoots and leaves of the bitter melon may also be eaten as greens”. I wonder how those compare to the fruit in bitterness…

Taxonomy

Momordica charantia is in the family Cucurbitaceae, along with cucumbers, melons, pumpkins, and squash.

Source

Sara picked up a bitter melon at the local 99 Ranch for $0.99/lb.

Method of Preparation

Parboiled slices of bitter melon
Parboiled slices

I cooked the bitter melon in a Chinese-style stir-fry with black bean sauce. (I think it’s Cantonese-style but I’m not quite sure, so I just say “Chinese-style”.) I basically followed this recipe with a few minor substitutions (garlic powder instead of fresh garlic because my garlic cloves all sprouted, etc.). I also put in a fair amount of diced Field Roast gluten loaf because Sara loves it and it could tip the balance from something gross and bitter to something she actually wants to eat. =)

I think parboiling in plenty of water is a crucial step in preparing this vegetable, because it extracts some of the bitter flavor and takes it down from “holy moly this is bitter!” to a milder bitterness more akin to unsweetened chocolate or coffee.

Bitter melon cooking in a pot with black bean sauce and Field Roast
Cooking with black bean sauce and Field Roast

The sauce came out pretty nice with the ingredients in that recipe. The chopped black beans thicken it up in lieu of any cornstarch or other thickener, which is nice.

Review

Plate with bitter melon stir-fry, haiga rice, and a side of kale
Served with haiga rice and a side of kale

Sara and I had tried bitter melon before, and she couldn’t eat more than a bite of it. It was simply too bitter. She recently bought it again hoping to find some way to enjoy it. I was worried she’d have the same reaction to this dish, but some combination of the parboiling and the spicy and savory sauce made it much more palatable. She enjoyed the “nice, filling texture” and even called the bitter melon “meaty”. She said it went well with the “strong spicy flavor from the garden [chili]” (I used manzano pepper Capsicum pubescens, which will certainly be the subject of another post), and overall found it “tasty with a surprising bitter aftertaste”.

Overall, I’d say before you write off bitter melon as something you’ll never try again because it’s too bitter, make sure you try preparing it by parboiling and cooking in a strong-flavored sauce.

Seaweed salad and very expensive books

Tonight I tried a seaweed salad I got at the grocery store (brand name seasnax). It was dried seaweed in a package that you’re supposed to rehydrate in cold water before eating. I mention it because the mix of seaweeds had two I’d never eaten (nor heard of) before. In addition to wakame (Undaria pinnatifida), “agar” (which can refer to a bunch of different species, mostly Gelidium and Gracilaria), and Irish moss (Chondrus crispus, listed as “tsunomata” on the package), all of which are familiar to me, it had “suginori” (Chondracanthus chamissoi), and “mafunori” (Gloiopeltis tenax). I honestly didn’t know which was which when I was eating the salad, so I can’t really comment on the flavor or texture of these new seaweeds. But anyway this is “eat every plant”, not “eat every red alga”, so seaweeds don’t count and the first real plant post will have to wait for another day.

I found what looks like a really comprehensive, authoritative book: Edible Medicinal and Non-Medicinal Plants. It has at least ten volumes, and it looks like each of them has a list price of over $200, making this one of the most expensive books I’ve ever seen. Fortunately, UC Berkeley has access to the electronic edition, so it can be accessed from any computer on campus (whether you’re a student or not). So this might be the basis of the main edible plant list!

BTW, it turns out that the index of Oxford Book of Food Plants is a pretty awful index. It’s full of typos, and some plants that have sections in the book are simply missing from the index. So I might end up having to go through the whole book and add things by hand…

Plant lists

Eating every edible plant part is easier said than done – so let’s at least say it before setting out to do it. I’m making it a “bucket list” goal to eat every edible part of every edible plant, not including those which shouldn’t be eaten because they’re so endangered, or are illegal or poisonous.

  • This includes only plants, not fungi (at least at first). Seaweeds are kind of a borderline case because they are “plants” in some senses but not others. I’ve eaten a “seaweed salad” at a Japanese restaurant that contained both nori and hijiki – it turns out that nori (a red alga) is more closely related to all land plants than hijiki (a brown alga) is related to either! But the quest is defined to include at least all so-called “land plants” (Embryophyta).
  • Endangered plants are included, but not parts of them that you can’t eat without harming the plant. So an endangered tree with edible fruit would be included, but an endangered plant with a single edible taproot would not. I won’t take part in eating anything to extinction.
  • Illegal plants are excluded. (Well, I might eat them anyway, but I won’t post on the internet about it.) If I can obtain it legally, I’ll eat it – for example, since I live in California I can just go to a grocery store and buy hemp (Cannabis sativa) seeds as food (hemp leaves, also edible, might be harder to come by…). If there’s no legal way for me to obtain something, it’s excluded.
  • Plants that are so poisonous or psychoactive that you can’t eat a reasonable portion without serious effects are excluded. For example, nutmeg is commonly used as a spice (even though a few tablespoons will send you on quite a trip), so it’s included, but Datura stramonium is excluded because although it’s certainly possible to eat some and not die, nobody eats it for the flavor. It’s squarely in the “drug” category rather than “food”.

With all that said, it seems like a good way to start upon my quest to eat every edible plant would be to begin compiling a list of every edible plant. What plant lists are out there?

One amazing resource is The Plant List, which aims to list every land plant (embryophyte). The Plant List’s 642 families contain 17,020 genera, which in turn contain over a million species (depending on how synonymous or questionable species names are counted). This is obviously much too large a list to start out with, and the majority of plants on it have no edible parts, but it’s reassuring to know that a definite, comprehensive list is available. The task is finite!

On the other hand, plucodes.com has a much more narrowly defined list which is also useful. PLU codes are those 4-digit (sometimes 5-digit) codes on the little stickers when you buy a piece of fruit at the grocery store. They’re also the codes you write on the bag or twist tie if you ever buy anything in bulk. Most produce items have a PLU code, even fairly exotic ones like arracacha or pitahaya (“dragon fruit”). It doesn’t include things like wheat or soybeans, because those aren’t often found in the produce section, so obviously it’s nowhere near a comprehensive list of all food plants.

You can download an Excel spreadsheet from that site with every standard PLU code, of which 1008 are actual varieties of produce. However, this does include many varieties of each item, such as 182 varieties of apple. The number of distinct “commodities” on the list is only 174, but that’s a start!

Another resource I might use in compiling lists is the index of The New Oxford Book of Food Plants. I haven’t yet entered these plants into a spreadsheet to see how many there are, but it seems like there ought to be all the ones that have PLU codes plus many more.

If you know of another list of edible plants (the more authoritative/canonical the better), I’d love to hear about it!

Just for fun, here’s a list of all the distinct commodities that have PLU codes (obviously the formatting is a little wonky):
ALFALFA SPROUTS, ALMONDS, ALOE VERA LEAVES, ANISE, APPLES, APPLE SLICES, APRICOTS, ARRACACH, ARTICHOKES, ARUGULA/ROCKET, ASPARAGUS, ATEMOYAS, AVOCADOS, BABACO, BANANAS, BASIL, BAY LEAVES, BEANS, BEAN SPROUTS, BEET GREENS, BEETS, BELGIAN ENDIVE (WITLOOF CHICORY), BERRIES, BITTER MELON/BITTER GOURD, Foo Qua, BOK CHOY (PAK CHOI), BONIATO, BORAGE, BRAZILNUTS, BREADFRUIT, BROCCOLI, BRUSSELS SPROUTS, CABBAGE, CACTUS LEAVES (Nopales/Cactus Pads), CACTUS PEAR (PRICKLY PEAR), CARAMBOLA (STARFRUIT), CARDOON (CARDONI), CARROTS, CASHEWS, CAULIFLOWER, CELERY, CELERY ROOT/CELERIAC, CHARD (SWISS CHARD)/SILVERBEET, CHERIMOYA, CHERRIES, CHERVIL, CHESTNUTS, CHICKPEAS, CHIVES, CHOY SUM/PAK CHOI SUM, CILANTRO (CHINESE PARSLEY/CORIANDER), COCONUTS, CORN, CUCUMBER, CURRANTS, DAIKON, DATES, DILL, EGGPLANT (AUBERGINE), ENDIVE/CHICORY, ESCAROLE/BATAVIAN CHICORY, FEIJOA, FENNEL, FENNEL LEAVES, FIDDLEHEAD FERNS, FIGS, FILBERTS, FRISEE, GAI (GUI) CHOY (CHINESE or INDIAN MUSTARD), GAI LAN, GARLIC, GINGER ROOT, GOBO ROOT/BURDOCK, GOURD, GRAPEFRUIT, GRAPES, GREENS, GUAVA, HOMLI FRUIT, HORSERADISH ROOT, JICAMA/YAM BEAN, KALE, KIWANO (HORNED MELON), KIWIFRUIT, KOHLRABI, KUMQUAT, LEEKS, LEMONGRASS, LEMONS, LETTUCE, LIMEQUATS, LIMES, LONGAN, LOQUATS, LOTUS ROOT, LYCHEES, MACADAMIA, MADROÑA, MALANGA, MAMEY, MANGO, MANGOSTEEN, MARJORAM, MELON, MINT, MIXED NUTS, MUSHROOMS, NAME, NECTARINE, OKRA, ONG CHOY, ONIONS, ORANGES, OREGANO, OYSTER PLANT/SALSIFY, PAPAYA/PAWPAW, PARSLEY, PARSLEY ROOT(HAMBURG PARSLEY), PARSNIP, PASSION FRUIT, PEACHES, PEANUTS, PEARS, PEAS, PECANS, PEPPERS (CAPSICUMS), PERSIMMON, PHYSALIS/CAPE GOOSEBERRY/GROUND CHERRY, PINEAPPLE, PINE NUTS (PIGNOLI), PISTACHIO, PITAHAYA, PLUMCOT (INTERSPECIFIC PLUM), PLUMS, POMEGRANATE, POTATO, PRUNES, PUMPKIN, QUINCE, RADICCHIO, RADISH, RAISINS, RAMBUTAN, RHUBARB, ROSEMARY, RUTABAGAS (SWEDE), SAGE, SALAD BAR, SAPODILLO/NISPERO, SAPOTE, SAVORY, SORREL, SOURSOP, SPINACH, SQUASH, SUGAR APPLE, SUGAR CANE, SUNCHOKES (JERUSALEM ARTICHOKES), SUNFLOWER SEEDS, SWEET POTATO/YAM/KUMARA, TAMARILLO, TAMARINDO, TANGELO, TANGERINES/MANDARINS, TARO ROOT (DASHEEN), TARRAGON, THYME, TOMATOES, TURNIP, VANILLA BEAN, WALNUTS, WATER CHESTNUTS, WATERCRESS, YUCA ROOT/CASSAVA/MANIOC, YU CHOY