Swiss Chard Companion Plants
Beta vulgaris var. cicla · goosefoot family · rotation group: leafy
The best companion plants for swiss chard are Radish, Buckwheat, Sweet Alyssum, Lettuce, and Onion. Avoid planting swiss chard near Beet, Spinach, Sweet Corn. Of the 11 pairings recorded here, 2 are supported by published research and 8 are traditional practice with no controlled evidence behind them.
What to plant with swiss chard
| Plant | Claimed benefit | Evidence | What the evidence actually shows |
|---|---|---|---|
| Buckwheat | Flowering buckwheat nearby recruits predators and parasitoids that suppress aphids on chard. | Research-backed | Extension cites trials showing buckwheat and cowpea raise predator and parasitoid numbers; the effect on chard aphids specifically has not been quantified. |
| Radish | Radish sown alongside chard acts as a preferred host that draws flea beetles away. | Research-backed | Radish and daikon trap cropping for flea beetles is supported by replicated trials and extension IPM guidance, though the published work used brassica cash crops; efficacy depends on sowing the trap 1-2 weeks early and devoting roughly 10% of the area to it. |
| Cabbage-family greens | Chard shares the cool-season bed with kale and cabbage without competing for the same rooting depth. | Traditional | Purely a spacing and scheduling convenience; no measured mutual benefit. |
| Dill | Dill flowers feed parasitic wasps and ladybugs that attack chard pests. | Traditional | Extension describes umbellifers as beneficial-insect habitat, but no controlled trial links dill to reduced pest damage on chard. |
| Lettuce | Lettuce fills the space between young chard plants and is harvested before chard needs the room. | Traditional | A sound spacing and succession tactic rather than a biological interaction; no trial data needed or found. |
| Onion | Onions are claimed to keep leafminers and aphids off neighbouring chard. | Traditional | No supporting trial found; the closest controlled test — leek grown with sweet pepper — found allium volatiles disrupted aphid feeding yet increased aphid survival and reproduction. |
| Sweet Alyssum | Alyssum's continuous bloom supports syrphid flies that prey on chard aphids. | Traditional | Consistent with the research-backed insectary principle, but no chard-specific trial was found. |
| Bush Bean | Beans are said to enrich the soil for leafy chard through nitrogen fixation. | Not supported | Fixed nitrogen stays overwhelmingly in the legume's own tissue during the season; reviews of isotope-tracer work find same-season belowground transfer to non-legume neighbours is small and inconsistent, with the real benefit arriving after residues decompose. |
What not to plant with swiss chard
| Plant | Claimed problem | Evidence | What the evidence actually shows |
|---|---|---|---|
| Beet | Beet is the same species as chard and shares its leafminer and Cercospora leaf spot. | Traditional | Grouping same-family crops concentrates shared pests and diseases — standard extension rotation advice — but the specific adjacency penalty has not been measured. |
| Spinach | Spinach hosts the same leafminer and shares chard's foliar disease complex. | Traditional | Same rotation logic as beet; sensible but unquantified. |
| Sweet Corn | Corn is said to shade out and outcompete chard. | Traditional | Shading by a tall neighbour is real, but this is generic competition rather than an established antagonism; chard actually tolerates part shade better than most crops. |
The honest verdict
Of everything gardeners recommend planting alongside swiss chard, 2 pairings have been tested properly: Radish, Buckwheat. Those are the ones worth planning your bed around.
The remaining 5 pairings on this page are traditional practice. They circulate on every companion planting chart online, but we could not find controlled evidence testing them. They are not wrong so much as unverified — most cost nothing to try, and interplanting flowers and herbs has its own well-documented benefit of pulling pollinators and predatory insects into the garden.
Widely repeated, not supported: Bush Bean — Fixed nitrogen stays overwhelmingly in the legume's own tissue during the season; reviews of isotope-tracer work find same-season belowground transfer to non-legume neighbours is small and inconsistent, with the real benefit arriving after residues decompose.
Every row above links to the publication it came from. See how we grade evidence.
Growing swiss chard: the numbers
| Sun | Full sun (6+ hours) |
|---|---|
| Water | Moderate |
| Spacing | 6 in apart · 14 in between rows · 4 per square foot |
| Mature size | about 20 in tall |
| Soil pH | 6–6.8 |
| Days to maturity | 40–55 days |
| Frost tolerance | Half-hardy — takes a light frost |
| Containers | Yes — 3 gallon minimum |
| Typical yield | continuous cut-and-come-again harvest, 8-12 lb per 10-ft row |
| Common pests | leafminers, aphids, flea beetles, slugs, caterpillars |
| Common diseases | Cercospora leaf spot, Alternaria leaf spot, bacterial leaf spot, downy mildew |
When to plant swiss chard
Zone 6b shownStart seeds indoors: Feb 27 – Mar 13 — 4–6 weeks before your last frost
Transplant outdoors: Mar 27 – Apr 9 — 2 weeks before last frost
Direct sow outdoors: Mar 27 – Apr 9 — 2 weeks before last frost
Expected harvest: May 6 – May 21 — 40–55 days from planting
Fall planting: Sep 29 – Oct 12 — 4 weeks before your first fall frost
Those dates are for zone 6b. Get your own dates by ZIP code →
Varieties worth knowing
seeds- Bright Lights — multicolour stems (gold, pink, orange), 40 days, ornamental and edible
- Fordhook Giant — broad white midrib, heavy yields, 42 days
- Ruby / Rhubarb — deep red stems and veins, 45 days
- Lucullus — light green heat-tolerant heirloom, 40 days
Variety names link to seeds on Amazon. As an Amazon Associate we earn from qualifying purchases. These are the varieties named in the extension sources for this crop, not a paid placement — where a source recommended a variety for a specific reason, that reason is the note beside it.
Put it in a bed
The garden planner checks every square against this ledger as you place crops — if you drop swiss chard next to something recorded as a bad neighbour, the square turns red and tells you why.
Records for the plants named above:
Same rotation group (leafy) — don't follow one with another:
Swiss Chard companion planting questions
What should not be planted next to swiss chard?
How far apart should swiss chard be planted?
Does companion planting with swiss chard actually work?
When should I plant swiss chard?
Sources for this record
- Home Garden Swiss Chard (C1039) — University of Georgia Extension
- How to Grow Swiss Chard in Your Garden — Utah State University Extension
- Arugula, Kale, Mesclun, Mustard, and Swiss Chard — Clemson Cooperative Extension HGIC
- Growing spinach and Swiss chard in home gardens — University of Minnesota Extension
Record compiled 2026-07. Spot an error or a study we missed? Tell us and we'll correct the entry.