
A graceful toyon at a botanic garden may have developed a cascading form on its own, planted under oak trees, but it has probably been aesthetically pruned to accentuate its shape.
Whenever I’m describing various garden tasks or techniques to beginners or nongardeners, inevitably someone asks, “Why go to all that trouble?” They suggest that in nature, seeds sprout and no one is paying attention to how deeply they’re planted, or what time of year, or whether they’re watered or protected.
The difference is that a garden is a relatively small, controlled environment. People impose limits and expect plants to perform in a predictable way. For example, if you let California poppies go to seed in a garden, you’d probably want to edit the profusion of poppy seedlings the next fall before they had a chance to crowd out everything else in your garden. You’d also cut back the poppies once the blooms had faded, rather than letting the dry foliage remain. You might also want to water them to prolong the bloom, especially if rains were few and far apart in winter and spring.