Entire healthy mature buckwheat plant in a real garden bed, showing growth habit and scale.Primary identification image. 60–120 cm tall, 20–20 cm wide at maturity.
3. FloweringWhite flowers from 4–5 weeks; beneficials visit.
4. TerminationCut or crimp before seed sets.
Growth stages are ordered chronologically; timing varies with cultivar, temperature, light and care.
Planting calendar for Portland, Oregon
direct sow 1–10 weeks after last frost; 30–45 days to maturity from sowing. Windows are derived from the region's average frost dates (last Apr 5, first Nov 5) and are estimates until you confirm your own dates in the calendar.
Plant
JanFebMarAprMayJunJulAugSepOctNovDec
BuckwheatFagopyrum esculentum
Text version of the planting timeline
Plant
Start indoors
Direct sow
Autumn sow
Transplant
Tend
Harvest
Buckwheat
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Apr 12–Jun 14 (estimate); Jun 14–Sep 22 (estimate)
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—
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May 12–Nov 5 (estimate)
Start indoorsDirect sowTransplantTendHarvestStriped bars are regional estimates; solid bars are dates you confirmed.
Direct sow: Apr 12 – Jun 14
Harvest: May 12 – Nov 5
Succession sow: Jun 14 – Sep 22
Spacing & support
In-row 10–15 cm; rows 15–15 cm. Planner footprint: 1 cell of 30 cm, 9 plants per cell.
Side-profile diagram of mature buckwheat: canopy 60–120 cm tall, 20–20 cm wide, shallow root zone, support and harvest-access envelope.
Soil & water
Soil
Any soil
pH
5.5–7
Fertility
low
Water
Moderate; tolerates poor soil.
Frost
tender; killed by frost
Support & training
No support structure needed.
Buckwheat mid-season before harvest, showing branching, vining, rosette or upright habit and space occupied.
Harvest signs
Cut at full flower, before seed sets (about 5–6 weeks)
Common problems
Pests: None common
Diseases: None common
Appearance alone is not a diagnosis; confirm with a regional extension guide.
Buckwheat is broadcast after the last frost into any warm soil and flowers within 30–45 days, reaching 60–120 cm. Its white flowers are strongly attractive to hoverflies, parasitic wasps and honeybees (Hogg et al. 2011), and it smothers weeds in empty beds between crops.
Buckwheat seed beside a ruler or coin for scale.
Buckwheat seedling at cotyledon and first-true-leaf stage, in soil, distinguishable from common weeds.
Buckwheat mid-season before harvest, showing branching, vining, rosette or upright habit and space occupied.
Cut it down when in full flower, before seed sets, or it self-sows everywhere; the soft residue decomposes fast. Buckwheat is frost-killed and can be sown every three weeks through summer to keep a flowering strip going. It is not a companion in the neighbour sense; it is a short-term insectary and cover crop.
Two or more mature buckwheat plants with a tape measure showing in-row spacing (10–15 cm).
Edible parts and safety
Edible: seeds (groats).
Buckwheat at end of season: seed head, dry pod, spent plant or removal stage.
Pests and diseases
Common pests: none of note. Common diseases: none of note. These vary by region; a photograph is an example, not a diagnosis. See the pest and disease guides and your local extension service.
Timeline
Season timeline for buckwheat: sowing, transplanting, flowering, harvest and bed occupancy aligned to frost dates.Text alternative: Direct sow Apr 12–Jun 14; Harvest May 12–Nov 5; Succession sow Jun 14–Sep 22.
We synthesize peer-reviewed research, university extension publications, and trusted horticulture resources. Our evidence levels help you understand how strong the science is behind the guidance.
Evidence tiers
Supported evidenceConsistent results from multiple robust studies
Traditional claimHistorical use reported, limited scientific support
Context dependentMixed or variable results across conditions
No verified relationshipNo reliable evidence identified
Spacing & support
Soil & water
Support & training
Harvest signs
Common problems
Container growing
Companion overview
Crop rotation
Sources, reviewer & update
