Is it chaotic? Yes. Deliberately so. This is guild planting. Guild planting, like all gardening, is a way of recreating nature -- but in order to take advantage of some of its processes.
Most ecosystems are mixtures of plants and animals, rather than vast monocultures. Why?
- each species uses slightly different resources (the 'ecological niche')
- each species has slightly different outputs, which are used by other elements in the system
- taller plants shelter tender young plants from extremes of weather
- not all species are susceptible to the same pests and diseases
- some species shelter pest predators
- potential exists for symbiotic relationships
Another idea of guild planting is to keep the ground covered by plantings all the time so as to minimise space for weeds to colonise, so that when one crop is pulled out, it should be replaced by another -- either by a new plant, or by a neighbouring plant growing bigger. In the picture above, you might be able to see radishes growing between the two rows of broad beans. They are a very fast-growing crop and I expect to pick them this week. The broad beans are now big enough to cope with root competition from weeds. The bok choy and the lettuces will also be eaten before the beans need the extra space.
And by the time the beans are out, it will be time for spring planting, which seems very far away!