Potato Companion Planting
Solanum tuberosum
Nightshade (Solanaceae) -- cool season
Good Companions for Potato
Bush beans supply nitrogen to nitrogen-demanding potato through biological N fixation. Research trials show 10-15% yield increase in potato when intercropped with bean in low-fertility soils.
Plant bush beans in every other row within the potato bed.
- Intercropping of potato with grain legumes -- European Journal of Agronomy (2005)
- Companion Planting with Potatoes -- Maine Cooperative Extension (2017)
Horseradish root exudates contain allyl isothiocyanate, a biofumigant that suppresses soil-borne pathogens including Verticillium dahliae and Rhizoctonia solani that affect potato.
Plant horseradish at the corners or ends of potato beds. Keep it contained -- horseradish spreads aggressively.
- Biofumigation potential of Brassicaceae and Alliaceae species -- Plant and Soil (2003)
Crops to Avoid Near Potato
Both are Solanaceae and share susceptibility to Phytophthora infestans (late blight), Alternaria solani (early blight), and Verticillium dahliae (verticillium wilt). Growing in proximity increases inoculum pressure for all three pathogens.
Separate tomato and potato in the garden. Also separate in crop rotation -- do not follow one with the other.
- Epidemiology of late blight (Phytophthora infestans) in tomato and potato -- Annual Review of Phytopathology (2009)
- Managing Late Blight in Tomato and Potato -- Cornell Cooperative Extension (2019)
Sunflower (Helianthus annuus) produces allelopathic compounds (chlorogenic acid, scopolin) in decomposing residues and root exudates that inhibit tuber development and reduce potato yield.
Do not follow sunflower with potato in rotation. Keep at separate ends of the garden.
- Allelopathic effect of sunflower on succeeding crops -- Allelopathy Journal (2006)
- Sunflower allelopathy for weed control -- Agronomy for Sustainable Development (2010)
Cucumbers and potatoes share susceptibility to Phytophthora infestans, and cucumber plants may serve as alternate hosts for potato-affecting strains. Proximity increases humidity and disease spread risk.
Separate in the garden layout. Ensure good air circulation around both crops.
- Phytophthora host range and crop management -- Plant Disease (2004)
- Managing Late Blight in Vegetable Gardens -- UMass Extension (2020)
Related Tools and Pages
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