Arca Seed Library

01 · Brief

Brief

Arca lends seeds instead of books. Members borrow in spring, grow the plant out, and bring seed back in autumn, so the collection grows every year it is used.

The library had 4,312 varieties in a card index, a paper ledger at the counter, and a different volunteer behind it every Saturday.

02 · Constraint

A new volunteer every Saturday.

Nobody behind the counter could be trained for more than ten minutes. The lending screen had to be obvious to someone who had never seen it, on a second-hand tablet, with soil on their hands: big targets, one action at a time, and an undo on everything.

03 · Process

How it came together

1. 01

   Reading the ledger

   Six years of handwritten loans showed which varieties came back, which didn’t, and that nobody had ever recorded germination. That became the shape of the catalogue.

2. 02

   The counter first

   We built lend-and-return before the public catalogue and ran it at the counter for a month, with the paper ledger kept alongside until nobody opened it.

3. 03

   A system small enough to keep

   Twenty-two components, one type family and a colour for each growing season. Volunteers who code can add a page without asking me.

04 · Build

The lending counter, running

The counter screen as a working component. Search a variety, lend a packet or take a return, and undo if you tapped the wrong one.

05 · Outcome

Outcome

to log a return at the counter (was a paper ledger)

~40 s

varieties catalogued, with growing notes

4,312

of spring loans came back as seed by November

61%

The public catalogue opened in October 2025, and two other seed libraries in the north have asked to run the same system.