What a seed lot code like 2L14 means
Daniel Pretorius · 5 min read · 28 August 2026
Pick up a pot in the shade house and you will often find a short code written on it in permanent marker: 2L14, 3R13, 1U15. It looks like shorthand, and it is, but it is not casual. Each code is a key into the seed register, the book I have kept alongside the plant register, and behind each code sits a row that records where that pot of seedlings actually came from. This is what the code means and how to read it.
Two registers, two kinds of record
The plant register records individual plants: each one has a number, and number 322 is one particular plant with its own history. The seed register records lots. A lot is not a single plant; it is one harvest of seed from one cross, sown together, with a quantity, a date and a code. The register now holds over twelve hundred lots, and more than seven hundred of them record an explicit cross: the mother plant first, the pollen parent second, joined by an X.
A single plant can only ever be itself. A lot becomes a pot of seedlings, then several pots, then bags at a sale, and through all of that the code on the pot is the one thread back to the row that says what the seed actually was.
Reading 2L14
The code has three parts, read right to left:
- 14 is the season: the seed was sown in 2014. Lots from 2011 onwards carry their year this way.
- L is the lot's letter within that season. Lots are lettered A to Z in the order they are recorded.
- 2 says which pass through the alphabet this is. A good season outruns twenty-six letters, so after 1Z the leading number ticks over and the letters start again at 2A. The 2014 season ran to 76 lots, which took it well into a third pass.
So 2L14 is the second run through the alphabet, letter L, in the 2014 season. Its row in the register reads: cross 322 X Mc Neel Green Girl, sown 8 October 2014. Most of that season's lots went into the ground on the same spring day, which is how sowing works here: the harvest comes in, and the lots go down together.
That row does more than name the cross. The mother is given by her number, and number 322 is a real plant in the plant register, a bronze with a green throat. Stand in front of a seedling from lot 2L14 and you can walk back to the exact plant that carried its seed. Each row also records the sowing date, the pots the seed went into, how many seeds the lot held, and the grower it came from; nearly all of the lots carry a sowing date, and a few hundred name their source.
The oldest codes, and an honest gap
The scheme was not born fully formed. The earliest lots, from the 2009 register, are coded with plain letters: A, B, C, and doubled letters when those ran out. The year and the cycle number came later, once the seasons started producing enough lots to need them.
And some codes did not survive the spreadsheet years. A code like 1E21 looks harmless to a person, but spreadsheet software reads it as scientific notation: one times ten to the power twenty-one. Type it into the wrong cell and the code silently becomes 1000000000000000000000, a number, not a lot. The E-series suffered exactly this. When the register was brought into the database, those mangled cells were set aside on a review list rather than guessed at; the E lots you can still look up today are the ones whose codes came through as text. The rule was simple: a record is either real or it is absent. Nothing was reconstructed by wishful thinking.
The honest consequence is that a few pots in the shade house carry only their handwritten label, with no surviving row behind it. And some rows are thinner than others: lot 1L14 has its code and its season, but no cross was recorded for it. Where that is the case, the listing says so, or says nothing. A blank in the register stays a blank on the page.
Why a breeder bothers
Clivia make you wait. A cross sown in October will not show its first flower for three to five years, and by then the marker ink has faded and memory has faded faster. The code is what survives the wait. It is the difference between a pot of orange seedlings and a pot of seedlings out of a known bronze green-throat mother, and that difference is the whole craft. When two seedlings from the same lot flower differently, the code is what lets me compare them against the same recorded parents and decide which one earns the next cross.
The code, continued
The system has not stopped with the marker pen. Today a harvested lot also gets a printed tag of its own, bound to the lot in the database, so a scan with a phone lands on the lot's record or its listing. But the printed tag is doing the same job the handwritten code has done since 2009: tying a living, growing thing back to the row that says what it is. When you see a code like 2L14 on a listing on this site, that is what you are looking at. Not shorthand. Provenance.