What Is Interplanting? Meaning, Benefits, and How-To

Interplanting is the practice of growing two or more different crops together in the same bed rather than in separate single-crop rows or blocks. It is the home-garden form of intercropping, closely tied to companion planting, and it is one of the easiest ways to cut pest pressure, use garden space more efficiently, and build healthier soil.^[1]

If you have only ever planted in tidy, separate rows, interplanting can feel like a leap. It is not. Below we explain what interplanting is, why it works, how it differs from companion planting and intercropping, and how to set up a Southern California garden that puts it to work.

What Is Interplanting?

Interplanting means growing more than one type of plant in the same area at the same time so the plants share space in a complementary way. Instead of a block of just carrots and a separate block of just radishes, you weave them together. Agricultural researchers call this broader practice intercropping, defined as growing two or more crops close enough to interact biologically, and you will also see it written as “inter-planting” or “intergrowing.”^[1]

The idea overlaps heavily with companion planting. Companion planting is intercropping done specifically because the plants are believed to help one another; interplanting is the hands-on spacing technique you use to put it into practice.^[4]

Why Is Interplanting Important?

Mixing crops does more than look lush. A diverse bed changes how pests, space, and soil behave.

Fewer pest problems

Many vegetable pests find their target plant by sight and smell, then settle in where that crop grows in a large, uniform patch. Mixing in other plants confuses that search and interferes with how pests move from plant to plant, and a varied bed offers more flowers and shelter for the beneficial insects that prey on pests.^[2] Be realistic about it: research finds intercropping reduces pest densities in roughly half of the cases studied, so treat it as a helpful edge rather than a guarantee.^[2] You can lean into it further with plants chosen to deter or distract common SoCal pests.

More harvest from the same space

Pairing plants that mature at different rates or occupy different layers lets a single bed use light, water, and nutrients more efficiently than growing each crop in its own patch, which can improve total yield.^[1] Fast crops like radishes or lettuce fill the gaps between slow growers and are harvested before the big plants need the room.^[6]

Healthier, better-used soil

Plants with different root structures draw water and nutrients from different layers of the soil profile instead of fighting over the same zone. Deep-rooted crops like tomatoes and melons pull from lower down while shallow-rooted crops use the surface.^[6] Interplanting nitrogen-fixing legumes such as beans alongside heavy feeders can also supply some nitrogen to their neighbors through root leakage and decomposition, easing fertilizer needs.^[3]

Interplanting vs. Companion Planting vs. Intercropping

These terms are used loosely and overlap, but here is the simplest way to keep them straight:

• Intercropping is the umbrella term: any time you grow two or more crops close enough to interact.^[1]
• Companion planting is the narrower idea that specific plants help each other when grown nearby.^[4]
• Interplanting is the home-garden technique of physically mixing those plants in one bed to carry it out.

So when people ask what it is called when two plants grow together on purpose, the answer is interplanting or intercropping, often guided by companion-planting principles.

How to Interplant Your Garden

You do not need a bigger garden to start, just a plan for how plants will share the bed.

• Mix root depths. Combine a shallow-rooted crop with a deep-rooted one so they are not competing in the same soil layer.^[6]
• Pair fast and slow crops. Sow quick harvests like radish or lettuce at the same time as long-season crops like carrots; the fast crop is picked before the slow one needs the space.^[4] This works hand in hand with succession planting.
• Use height in layers. Let tall plants such as tomatoes, corn, or trellised beans shade cool-season greens that would otherwise bolt in Southern California heat, stretching their season.
• Do not overcrowd. Interplanting fills space, but each plant still needs light, air, and water. Give roots and leaves enough room to avoid disease.

For a season-by-season plan of what to combine, see our guide to the Southern California vegetable garden.

Good Interplanting Combinations for Southern California

Start with pairings that are documented rather than garden folklore:

• The Three Sisters: corn, pole beans, and squash. The corn supports the vining beans, the beans fix nitrogen, and the squash shades the soil as a living mulch.^[6] It is a time-tested traditional system, though formal trials have not proven it out-yields growing the three crops separately, so grow it for its structure and heritage.
• Radishes between carrots: sow the quick radishes and slow carrots together so the radishes are harvested before the carrots fill in.^[4]
• Flowers among vegetables: in one study, marigolds and sweet alyssum planted with squash increased the natural enemies of aphids and slightly improved yield, a research-backed reason to tuck flowers into the veg bed.^[6]

A quick honest note on tradition: classic guides pair onions with carrots to repel each other’s pests, but extension reviews find little research supporting allium pest-repellence claims, and some trials contradict them.^[5][6][8] Plant such pairings for space-sharing, and lean on the combinations above when you want a research-backed benefit.

Want more pairings? Browse our list of companion plants that grow well together in a SoCal garden.

When Not to Interplant

Interplanting is not always the answer. Crowding plants too tightly makes them compete for light, water, and nutrients and can raise disease pressure, so give each crop room even when you mix them. And not every pairing delivers a real benefit: many companion charts online are anecdotal rather than tested, so lean on documented combinations instead of trusting every list you find.^[7]

Interplanting rewards a little planning with a fuller, tougher, more productive garden. Stop by any Green Thumb Nursery location and our team can help you pick combinations suited to your beds and the season.

Interplanting FAQ

What is interplanting?

Interplanting is growing two or more different crops together in the same space at the same time, rather than in separate single-crop rows. It is the home-garden form of intercropping and is closely tied to companion planting.^[1]

What does interplant mean?

To interplant means to set different plants among one another in the same bed so they share space in a complementary way, for example tucking fast-growing radishes between slower carrots.

Is interplanting the same as companion planting?

They are closely related but not identical. Companion planting is the idea that certain plants help each other nearby; interplanting (intercropping) is the technique of actually mixing those plants in one bed to apply it.^[4]

What is it called when two plants grow together?

Deliberately growing two or more plants together in the same space is called interplanting or intercropping. When it is done specifically to help the plants, it follows companion-planting principles.

Is interplanting the same as intercropping?

Essentially yes. Intercropping is the broad term for growing two or more crops in close proximity; interplanting is the everyday home-garden version of it.^[1]

What are good interplanting combinations?

Documented options include the Three Sisters (corn, beans, squash), radishes sown between slow carrots, and flowers like marigolds or sweet alyssum among vegetables to draw in beneficial insects.^[6]

Sources

• SARE (USDA), Guidelines for Intercropping: sare.org
• SARE (USDA), Using Intercropping to Disrupt Host Finding: sare.org
• SARE (USDA), Intercropping Legumes with Nonlegumes: sare.org
• University of Maryland Extension, Vegetable Succession and Companion Planting: extension.umd.edu
• University of Minnesota Extension, Companion Planting in Home Gardens: extension.umn.edu
• University of Illinois Extension, Companion Planting (Good Growing, 2025): extension.illinois.edu
• University of Illinois Extension, Companion Planting: Anecdotal or Tried and Tested? (2015): extension.illinois.edu
• UC ANR Master Gardeners, Better Together: The New Science of Companion Planting (2022): ucanr.edu

Written by David S.

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