One of the container planters Boucher-Colbert will soon use on Rocket’s roof space (see "Let A Thousand Balconies Bloom") is what he calls a “pillow pack”—essentially a bag of potting soil that’s been insulated from extreme temperatures, enriched with nutrients, then planted with a healthy vegetable start.
This do-it-yourself set-up is cheap to put together and will result in big yields, especially in full sun. Boucher-Colbert likes growing fruiting crops like peppers, eggplant or even tomatoes with this method. Starts that are ready to transplant have been growing about two months, he says, so at this point in the growing season, buying them from your favorite farmer or nursery may be the best option.
Look for starts that are vibrant, green and healthy. Boucher-Colbert says yellow leaves can signal nutrient deficiency and whitening leaves could be the result of sunburn (taking plants too fast from fluorescent to natural lighting). When buying a six-pack of plants, look for single plants per cell, and if you tug one of the plants out, it should take all the soil with it and show a healthy root spread.
For the planter, you’ll need a bag of potting soil, bubble wrap, a shiny Mylar emergency blanket (heavy aluminum foil will also work) and waterproof tape.
Find a place to put the bag for the rest of the season. Consider a deck, a stable, weight-bearing rooftop or concrete surface that gets sunlight and can be easily reached for watering and drainage.
It’s easiest to insulate the bag first. For ease, bring the bag to the place where it will be growing all season—it can be unwieldy to lug around. Wrap the bag in the bubble wrap (1) and use tape to seal sides and top seams (2). Do the same with the emergency blanket or foil (3). It should look like a shiny pillow when you’re done.
Cut two X-shaped openings (4) into each bag, spaced evenly between the ends of the bag. To enrich the soil, add a handful of bone meal to each opening and stir into the soil. Then plant your start, which should be at least four to six inches tall.