• May 18th, 2024
  • Saturday, 10:14:44 AM

Maximizing Vegetable Harvest Without Increasing Space

Photo: Denver Botanic Gardens/ Scott Dressel-Martin The Denver Botanic Gardens offers professional tips for sucessful gardening.

Brien Darby


Cultivating vegetables is a practice as ancient as civilization and one that is mostly unique to the human species. Our earliest settlements were only successful because we gained the skills necessary to grow food, slowly replacing our hunter-gatherer lifestyle. In modern times, we have the luxury of purchasing most of our food, but many of us still have the primal, instinctual urge to grow where we live–enter the modern home vegetable garden. However, unless you have traded your lawn for garden beds, most of us are limited on space. Whether you grow in a community garden plot, a corner of your own property, raised beds or containers, these strategies will help save space and maximize your harvest without adding extra square footage.

In Colorado, we divide our annual vegetable crops into two categories based on whether they are planted in the cool seasons (spring and fall) or the warm season (summer). Cool season crops like radishes, lettuce, spinach and peas can be sown as early as mid-March. These crops can be planted again in the late summer for harvest throughout the fall. The warm season usually starts around the end of May and this is when plants that can be damaged by frost (like tomatoes, peppers, squash and cucumbers) are transplanted or sown.

Cultivating vegetables is a practice as ancient as civilization and one that is mostly unique to the human species.

Our first strategy is called succession planting. Many cool season crops mature quickly and can be planted multiple times before the warm season begins. For example, radishes and leaf lettuce sown on April 1 will be ready for harvest around May 1. To extend the harvest of these crops, plant one row of each crop every week of April. The rows will mature at different times and will extend the harvest all throughout May. Cool season crops suffer in warm temperatures, so they can be fully removed once harvested to make room for warm season crops.

Another useful space-saving strategy borrowed from urban agriculture is called intercropping. In this system, plants of different species are grown close to one another in a way that does not introduce competition. For example, rows of carrots, beets and other root vegetables can be intermixed with quick-growing crops with shallow roots like lettuce and arugula. The salad greens mostly grow above ground while the root crops fill the space below the surface of the soil.

Encouraging plants to grow vertically is crucial for saving space in small gardens. Trellising is the act of providing structural support for vining crops like cucumbers, melons and pole beans, and for crops with heavy fruits like tomatoes. While there are many prefabricated trellis options, they can also be made from upcycled materials. A truly ingenious system of trellising is to allow crops to climb up other crops; corn stalks and sunflowers can provide stability to pole beans or small-fruited vining squash.

One of the simplest trellising systems, called the Florida weave, is used commercially to grow tomatoes. In this system, T-posts are placed six feet apart in rows with tomato plants spaced between. As the plants grow, twine is stretched across the posts in a manner that “sandwiches” the plants in place. Commercial growers remove the lower limbs of tomatoes to prevent fruit from laying on the ground; this creates space for shorter crops like lettuce and basil to grow at the base of the tomatoes.

In addition to saving space, trellising helps protect fruits and vegetables from attacks by ground critters like insects, mice and rabbits. If a trellis is placed at an angle to the ground (rather than perpendicular), it can also provide shade for cool season crops that can grow underneath.

Lastly, choosing varieties with either short days to maturity or that have more compact growing habits can help save space and increase your overall harvest. The average days to maturity for a variety is usually listed in seed catalogues, on seed packets and on nursery plant labels. To find compact varieties of vegetable plants, look for ones that are marketed as container plants. Determinant tomatoes (those that set all their fruit at once) and most spicy peppers are also naturally smaller than other varieties. Happy gardening!


Brien Darby, Manager of Urban Food Programs. Content provided by the Denver Botanic Gardens.