This year I'll add poblano peppers and maybe one or two others. If the soil has been enriched, these plants can be planted closer together than most authorities recommend. In fact, close planting can help cut down on weeding by shading most of the unplanted ground. Winter and summer squashes, on the other hand, need lebensraum . Be it acorn, butternut or zucchini, these plants live to sprawl, stretch out, expand.
Cucumbers are similar, but they can be trained to climb a trellis.
Allow at least several feet around squash plants. Tomatillos, the tangy green tomato-like fruit with the papery husk which is an essential ingredient of Mexican salsa verde, also grow on sprawling plants. I found out last year that tomatillo plants are very prolific. Two are probably more than adequate for any household's Mexican palate needs. With small space gardening, most of the work is front-loaded.