Square inch gardening

"Square inch gardening" is a term coined to describe the method of growing many plants packed closely together, emulating how plants grow in nature. 

So if you have a small space for gardening, growing plants more closely together than recommended by seed packets may be beneficial. Sow your seeds very close together; in nature seeds don't measure distances in inches as is recommended on backs of seed packages. Spacing plants closer together acts like a "living mulch" - preventing evaporation from the soil and saving watering costs. We also plant multiple-layers. For instance, bigger vegetables like broccoli or peppers are planted with a carpet of greens - lettuce, arugula, etc., underneath. With this type of technique the green carpet acts like a living mulch, preventing weeds and keeping the soil moist.

This method of growing requires one to experiment since each garden's growing conditions are different. But you'll be rewarded with increased yields!