How to Grow Potato

Broad bean root nodules fix 40-60 kg of atmospheric nitrogen per hectare via Rhizobium leguminosarum, making it available to neighbouring potato plants through soil microbial pathways. The tall bean stems also provide a partial windbreak for potato foliage.

Pea roots host nitrogen-fixing Rhizobium bacteria that enrich the soil with plant-available nitrogen, directly benefiting heavy-feeding potato tubers. Cut pea haulms at ground level after harvest to leave nitrogen deposits undisturbed.

French marigold roots release alpha-terthienyl, a compound toxic to root-knot nematodes (Meloidogyne spp.) that damage potato tubers. Interplant marigolds throughout the potato bed — the effect is strongest after 2-3 months of root growth.

Thyme releases thymol vapours that repel Colorado potato beetles, which locate host plants by scent. Plant creeping thyme between potato rows as a fragrant ground cover that disrupts beetle navigation.

Potatoes and tomatoes are both highly susceptible to late blight (Phytophthora infestans) — airborne spores from one crop will rapidly infect the other. Keep at least 5 metres apart and never grow them in the same bed or in sequence without a 3-year gap.

Cucumbers and potatoes compete for potassium in the topsoil, and their combined foliage density creates a humid microclimate that promotes fungal diseases in both crops. Keep them in separate beds with good airflow between.

Pumpkin vines sprawl over potato hills and smother foliage needed for tuber development, while both crops are heavy potassium feeders that deplete the soil together. Grow them in separate beds at least 2 metres apart.

Courgettes and potatoes both demand heavy potassium feeding and their dense combined canopy traps moisture, promoting Phytophthora and downy mildew. Grow them in well-separated beds with open airflow.

Winter squash vines smother potato foliage and compete for the same potassium and phosphorus reserves. Both also harbour Verticillium wilt in their root zones, creating mutual reinfection risk. Keep in separate beds.

Celery and potatoes compete intensely for the same soil moisture band and both require consistent irrigation — growing them together makes water management difficult without overwatering one or underwatering the other.

Potato earthing-up and harvesting disturbs the shallow asparagus crown roots that sit just 15 cm below the surface, causing lasting damage to the perennial root system. Never interplant — asparagus beds must remain undisturbed for 15+ years.