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Growing Soybean in Knoxville

🇺🇸 Zone 5 Planting Guide · Humid subtropical climate

USDA Zone 5 215 frost-free days 80-120 days to harvest

Quick Answer: Growing Soybean in Knoxville

Yes, you can grow Soybean in Knoxville, US! Plant during Apr, May, Jun, Jul for best results. Knoxville is in USDA Zone 5 with a Humid subtropical climate, offering 215 frost-free days per year. The difficulty level is medium, and Soybean takes 80-120 days to harvest. Soybean needs full sun and regular watering.

Climate Match Analysis

Moderate Match Knoxville + Soybean

Knoxville's climate requires careful timing. Winter lows (-2°C) drop below Soybean's minimum (10°C), so avoid cold months. Follow the recommended planting months for success.

Soybean tolerates 10°C to 35°C
Optimal: 20°C - 30°C
Knoxville range -2°C to 31°C

Knoxville Climate Data

USDA Zone
5
Frost-Free
215days
Winter Low
-2°C
Summer High
31°C
Rainfall
1245mm/yr
Climate
Cfa
Humid subtropical

Soybean Planting Calendar for Knoxville

Green months show the best time to plant Soybean in Knoxville

Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Plant Soybean Not recommended

Soybean Growing Requirements

☀️

Sunlight

Full Sun

6+ hours direct sunlight

💧

Water

Regular

Consistent moisture, 1-2 inches/week

📅

Days to Harvest

80-120

From planting to first harvest

📊

Difficulty

medium

Some experience helpful

💡 Growing Tips for Soybean

Inoculate seeds with nitrogen-fixing bacteria. Bush types don't need support. Wait until soil warms to at least 20°C before transplanting outdoors — cold soil stunts growth and can invite root rot. Aim for about 2.5 cm of water per week, adjusting for rainfall. Organic mulch around the base helps maintain even moisture.

Frost tolerance: Soybean is NOT frost tolerant — wait until after the last frost in Knoxville.

How to Grow Soybean in Knoxville

Knoxville, US is in USDA Hardiness Zone 5 with a Humid subtropical climate (Köppen Cfa). With winter lows of -2°C and summer highs of 31°C, the growing season spans approximately 215 frost-free days. Soybean grows well with some gardening knowledge in this climate.

Soybean thrives in temperatures between 20°C and 30°C, requiring full sun and regular watering. In Knoxville, the best months to plant Soybean are April, May, June, July. Soybean is not frost tolerant, so it's important to wait until after the last spring frost before transplanting outdoors. Expect to harvest in approximately 80-120 days after planting.

Knoxville receives 1245mm of annual rainfall, which provides good natural moisture for Soybean. Supplement with additional watering during dry spells.

Other Plants That Grow in Knoxville

More plants you can grow alongside Soybean in Knoxville

Keep Exploring

Frequently Asked Questions

Can I grow soybean in Knoxville?

Yes! Soybean can be successfully grown in Knoxville, US. Knoxville is in USDA Hardiness Zone 5 with a Humid subtropical climate. The difficulty level for growing Soybean here is rated "medium". The best months to plant are April, May, June, July.

When should I plant soybean in Knoxville?

In Knoxville, the recommended planting months for Soybean are April, May, June, July. Knoxville has 215 frost-free days per year, with winter lows of -2°C and summer highs of 31°C. Since Soybean is not frost tolerant, make sure to plant after the last frost date.

How long does soybean take to grow in Knoxville?

Soybean typically takes 80-120 days from planting to harvest. In Knoxville's Humid subtropical climate with 215 frost-free days, you have plenty of time to grow Soybean to maturity. Inoculate seeds with nitrogen-fixing bacteria. Bush types don't need support. Wait until soil warms to at least 20°C before transplanting outdoors — cold soil stunts growth and can invite root rot. Aim for about 2.5 cm of water per week, adjusting for rainfall. Organic mulch around the base helps maintain even moisture.

Can I grow soybean indoors in Knoxville?

Soybean can potentially be grown indoors in Knoxville with proper conditions. It requires full sun (6+ hours of direct light — a south-facing window or grow lights recommended). Indoor growing extends your season beyond the Apr, May, Jun, Jul outdoor planting window. Use containers with good drainage and regular watering.

What month do I plant soybean in Knoxville?

Plant Soybean in Knoxville during April, May, June, July. These are the optimal months based on Knoxville's USDA Zone 5 climate, 215 frost-free days, and temperature range of -2°C to 31°C.

Is soybean hard to grow in Knoxville?

Soybean is rated "medium" to grow in Knoxville. Some gardening experience is helpful. Pay attention to watering schedules and planting timing. The climate match for Soybean in Knoxville is Moderate.

What grows well with soybean in Knoxville?

In Knoxville, you can grow many companion plants alongside Soybean. Good options from the same planting window include Tomato, Basil, Lettuce, Carrot and 2 more. These plants share similar planting months and thrive in Knoxville's Zone 5 climate.

Does soybean need full sun in Knoxville?

Soybean requires full sun. In Knoxville, provide at least 6 hours of direct sunlight daily. Most garden locations with southern exposure will work well.

Last updated: March 2026 · Climate data from NOAA, FAO, USDA

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