Early planting
After mid-MayBZL’s German guidance places frost-sensitive slips after the mid-May Eisheiligen period; the Rieste farm date is not published.
Documented production-area guide · Rieste · Lower Saxony
Sweet potatoes are grown commercially near Rieste, Lower Saxony, and a Lower Saxony state-trial program reported successful cultivation. The grower’s exact transplant date is not published.
Lower Saxony · Rieste production reference point
Growing for a home garden? See the general sweet potato guide.

Regional crop context
The Lower Saxony Chamber of Agriculture documents a commercial producer at Rieste and reports a successful 2018–2020 state trial program. This confirms local cultivation, not uniform suitability across the state.
The climate panel is a Rieste reference point. BZL’s post-mid-May timing is national guidance; the local grower’s exact planting calendar is not publicly stated in the sources reviewed.
Step 1 of 7 · Assess
Coordinate slip supply, bed warming, irrigation and the fall harvest plan. The page uses a named Lower Saxony production location rather than the national Germany climate average.
6 topics still to verify· planning aid only, not a suitability score
Selections stay in this browser tab and are not saved or sent anywhere.
Need a field-specific review? Run a coordinate-level farm audit for localized conditions.
Root-knot nematodes, wireworms and other soilborne pests affect marketable roots. Soil sampling, clean planting material, crop rotation and equipment sanitation are the first decisions; chemical treatment depends on current field results and product labels.
Step 2 of 7 · Plan
Use the documented post-mid-May regional planning period as a starting point. The month strip marks May and June as source-supported planning months and shows local 1996–2025 temperature context.
BZL’s German guidance places frost-sensitive slips after the mid-May Eisheiligen period; the Rieste farm date is not published.
Use the local warm-season climate with the chosen cultivar’s 90–120-day cycle; this is a climate-informed planning range, not a reported Rieste transplant schedule.
Historical regional climate
Green tiles are months whose mean soil temperature is in the 77–86°F root-development range; all other tiles are neutral and show the value. Early, main and late badges mark the 10th, median and 90th-percentile dates for reaching 18.3°C for 4 consecutive days. Bar height shows the mean.
Early soil-warming date
May 16
10th percentile
Median soil-warming date
June 10
median year
Late soil-warming date
June 30
90th percentile
Months whose historical mean soil temperature reaches the 65°F reference: July, August. Months in the 77–86°F root-development range: none in the available record. These are monthly regional averages, not planting dates or a frost check.
Open-Meteo · era5_land · 1996-01-01 to 2025-12-31 · Reference point 52.48°N, 7.98°E. Soil-temperature values are modeled at 0–7 cm model layer; the 65°F (18.3°C) transplant reference comes from a 4-inch field measurement. Use the regional calendar above with a current field reading.
Sweet potato slips establish best after frost risk has passed and the soil is at least 65°F (18.3°C) at 4 inches. That is a field measurement; the climate strip above shows regional history.
Use the regional crop duration and expected fall cutoff to choose a variety and harvest date. Confirm market grade, digging capacity and curing space before planting.
Step 3 of 7 · Prepare
Shape loose, well-drained beds and manage moisture through establishment. Select soil texture and equipment based on the intended market grade and harvest method.
Keep bed height and shape consistent with soil texture, water movement and the equipment used on the farm.

Base pH and fertilizer rates on representative soil tests. Avoid excess nitrogen, which can favor vine growth over marketable storage-root sizing.
Step 4 of 7 · Establish
Sweet potatoes are established from vegetative vine cuttings called slips. Buy clean, healthy slips in the target variety and quantity, and keep them shaded and moist until planting.

Use the 80–100 × 20–30 cm European field-trial envelope as a crop-level starting range; adjust within bounds for equipment and market grade.
Planting calculator
Estimated slips
44,444
at 90 × 25 cm
Estimate = field area ÷ row-by-slip spacing. Keep values within the published bounds, then match the starting pattern to equipment and target root grade. Headlands and replant allowance are not included.
Step 5 of 7 · Manage
The first weeks determine how evenly slips establish and how the crop competes. Protect the crop from early weed competition and scout for wireworms, flea beetles and root-knot nematodes. Use field history, clean planting material and equipment sanitation to reduce avoidable risk.
Water immediately after setting and maintain enough moisture for root establishment. Track rainfall and soil moisture; avoid keeping beds saturated.
Scout early and maintain a weed-free start through canopy closure. Choose current control methods for the farm’s production system.
Wireworms, flea beetles and root-knot nematodes can downgrade roots. Keep field history and scouting records tied to each harvest lot.
Use certified or otherwise clean slips, avoid carrying soil on slips, and clean equipment after infested fields to limit movement of nematodes and soilborne disease.
Step 6 of 7 · Harvest
The Lower Saxony Chamber of Agriculture reports harvest starting shortly before the first frosts, around early October. BZL gives a 90–120-day crop cycle as national crop context.

Harvest period
Plan by variety, market size, planting date, field condition and frost risk.
Cure
A crop-level curing reference is 7–10 days with airflow; use the facility and buyer protocol for the harvested lot.
Store
Maintain stable temperature, humidity and ventilation after curing.
Step 7 of 7 · Reference
Successful 2018–2020 trials, small-farm production and early-October harvest context.
Identifies the Strampe farm at Rieste and marketed organic sweet potatoes; no exact transplant date is given.
National post-mid-May planting guidance and 90–120-day crop duration; not a farm-specific Rieste calendar.
European field trial comparing 80 × 20, 80 × 30, 100 × 20 and 100 × 30 cm row-by-plant spacing. Used as a crop-level spacing reference, not a local calendar.
Crop-level soil-temperature context, bed preparation, equipment-led row spacing and the relationship between plant density and root size.
Crop-level transplant establishment, slips, frost sensitivity and raised-bed practice. Missouri calendar dates are not applied to other regions.
Shared crop-level reference for curing and storage conditions. Its Texas planting calendar is used only on the Texas page.
Photo authorship and licence information are recorded centrally. View photo credits.