Acorn squash
Cucurbita pepo
Also known asPepper squash · Des Moines squash · Table queen squash
Environment
The bounded range this crop tolerates.
Climate and zones
- USDA zones
- 3–12 (winter low around -40°C)
- Frost
- frost sensitive (dies at first frost)
- Season
- warm (summer, frost-sensitive)
Growing systems
Root mass: heavy. Thin-channel systems can't hold this crop.
Growing media
| Medium | pH effect | Retention | Bacterial surface |
|---|---|---|---|
| Soil-based mix (Potting soil) | varies | high | high |
Nutrient demand by stage
NPK ratios are relative weights. EC targets shift through the plant's life.
| Stage | N | P | K | EC (mS/cm) |
|---|---|---|---|---|
| seedling | 2 | 1 | 1 | 1.2 |
| vegetative | 3 | 1 | 2 | 1.8 |
| flowering | 1 | 2 | 3 | 2 |
| fruiting | 1 | 2 | 3 | 2.2 |
Companion-growing notes
- Heavy uptake of potassium, nitrogen. Co-grown crops with the same demand will end up deficient even at "correct" EC.
- High transpiration. Regular reservoir top-ups needed during fruiting.
Aquaponics suitability
Compatible
Fish waste provides enough nitrogen for healthy growth. Supplemental potassium, calcium, and iron may still be needed depending on fish stocking density.
Care notes
A demanding crop for soilless culture because of vine size and the pollination step. It does best in Dutch bucket or large container setups with a strong trellis for vertical training. Hold EC around 1.8-2.4 mS/cm, leaning to the top of that band during fruiting, and pH near 5.8-6.5. Run daytime temperatures around 20–30°C with nights no colder than about 15°C. It needs full sun or strong supplemental light, on the order of 20-30 mol/m2/day. Feeding is heavy, with potassium demand rising once flowers appear, plus steady calcium through fruiting. Indoors there are no pollinators, so move pollen by hand: the male flower sits on a thin straight stalk, the female has a small swelling (the immature fruit) at its base, and a soft brush or cotton swab transfers pollen best in the morning while flowers are open. Expect on the order of five fruits per plant, ripe when the rind hardens and the stem dries, roughly 80 to 100 days after transplant. Each fruit is light, near 0.5–1 kg, but a loaded vine still needs firm support, and mesh slings help once fruits reach tennis-ball size. Powdery mildew is the usual disease; airflow and dry foliage reduce it. Allow one to two square metres per plant. Underplanting lettuce or herbs below the trellis uses the floor space. Check EC weekly during fruiting, since the reservoir draws down faster than expected.