Every plant here is grown live from a Lindenmayer system — 1968's idea that a plant is a set of instructions, rewritten at every tip. No two come out the same.
Click anywhere on the ground to plant your own
How it grows
In 1968 the Hungarian biologist Aristid Lindenmayer (1925–1989) published a way to describe how simple organisms develop — first in the two-part paper Mathematical models for cellular interactions in development, in the Journal of Theoretical Biology. He was studying the growth of filamentous algae and bacteria, among them the cyanobacterium Anabaena catenula, and wanted a notation for cells that divide and change all at once.
His answer is now called an L-system. You start with a short string of symbols — the axiom — and a set of production rules, each saying what one symbol becomes. Then you rewrite every symbol at the same time, again and again. That simultaneous rewriting is the whole trick: it mirrors many cells dividing in one step, which is exactly what an ordinary grammar cannot do.
To turn a string into a picture, the symbols steer a "turtle" that draws as it walks — an interpretation popularised by Przemysław Prusinkiewicz and gathered, with Lindenmayer, in the 1990 book The Algorithmic Beauty of Plants. The brackets [ and ] save and restore the turtle's position, which is how one line learns to branch.
XF+[[X]-X]-F[-FX]+XFF
The turtle alphabet
F draw forward + turn left - turn right
[ save spot ] return X a growth point, drawn as nothing.
Each seed picks one of several classic rule sets, jitters its angle and segment length, and is scaled to fit — so the family resemblance holds while every individual differs. Your garden and the season are saved in this browser; they will be here when you return. The bee is procedural too, and keeps an eye on whatever is growing.