Communal jams.

It is perhaps not surprising to hear that people who devote half their Sunday to making and sharing fruit jam with a bunch of strangers are really nice. But I didn't know what to expect this past weekend when I attended the Fourth Annual Public Fruit Jam at Machine Project in Echo Park, hosted by Fallen Fruit Collective, a group that organizes occasional public fruit-gathering walks in LA. I had a great time and learned a lot, so in the spirit of sharing, here are some of the tips I picked up.

DO bring fruit to share from your own trees or that you've gathered from public land (in parks, hanging over sidewalks, etc.). I saw bags of homegrown oranges, crabapples, jujubes, lemons, nectarines and tiny plums the size of cherries. Jessica (my jam-making partner in crime) and I ended up incorporating everything but the jujubes into the second jam we made.

Raspberries, peaches, lemon verbena and lemon zest.

DO set aside any special fruit you want to use for your own jam. Jessica had made a stop at the Atwater Farmers Market that morning and the first jam we made used all the raspberries and peaches she bought, along with lemon zest from some shared lemons and the lemon verbena I had clipped from my backyard.

But DON'T be a jerk and if someone asks if they can have a little of what you brought, DO share. A woman sitting next to us had brought a piece of ginger she was mostly using for herself, but she kindly gave us a knob when we asked.

Cooking the jam.

DO fill the bowl you're given with chopped fruit. The proportions are somewhat flexible, but you'll need about five cups of fruit, five cups of sugar and one packet of pectin to make about four small jars of jam. You cook the jam by yourself, with the assistance of the jam-making experts floating around, but it makes it easier for them to guide you if you start with the correct proportions.

DON'T just chop up a little bit of everything and throw it into a bowl to become an unappetizing pile of mush. Remember finger-painting in kindergarten? When you thought mixing every color together would result in the most beautiful color ever, but instead turned a mucky, ugly brown? It's like that. DO have a plan, even a vague one.

Simmering plum-nectarine-citrus-basil jam.

But DON'T be afraid to experiment. The second jam we made included plums, crabapples, nectarines, basil, oranges, grapefruit and ginger. Sounds like a scary mess, but it's actually quite good: slightly bitter from the grapefruit, sweet from the stone fruit, a tiny bit gingery and tinted a lovely coral hue.

Plum-jam-maker standing in front of us. Love the matching apron!

Perhaps most important: DO talk to the people around you! We met a father and son from Culver City who were there because the son, who was around ten years old, loves gardening and cooking. I wish I had been that awesome as a kid. Standing in line for the cooking stations outside, we befriended the people ahead of and behind us, which made the 30-40 minute wait bearable, and we ended up swapping jars of jam with them at the end. (And regarding the line, DO wear sunscreen and DO get there early, so you aren't waiting outside under the relentless afternoon sun.)

Clockwise from top: blueberry-lemon-mint, plum-citrus-basil, raspberry-peach-lemon verbena.

Finally, DO leave a jar of your jam for the communal archives and DON'T be afraid to enjoy the rest yourself! Stored in the refrigerator, the jam will keep for 2-3 weeks, longer if frozen. I've been slathering it on toast and PB & J sandwiches and mixing it into Greek yogurt at breakfast. I've also been peeking covertly at the pretty row of jars in the fridge, remembering one of my favorite passages from the canning chapter in my grandmother's old edition of the Joy of Cooking:

"I should like to begin my chapter with the assurance that it is a thrill to possess shelves well stocked with home-canned food. In fact, you will find their inspection (often surreptitious), and the pleasure of serving the fruits of your labors, comparable only to a clear conscience or a very becoming hat."

So true.