Peanuts are a warm-season legume whose flowers send pegs down into the soil, where the pods develop underground. Utah State University Extension notes that if a peg does not penetrate or get covered, the pods will not develop and produce seeds, so soil prep and hilling matter. Days to maturity range from 90 to 165 depending on type.
Peanut at a glance
| Type | Vegetable |
|---|---|
| Season | Warm-season |
| Sun | Full sun |
| Plant spacing | 18 in |
| Row spacing | 24 in |
| Per square foot | 1 |
| Seed depth | 1.5 in |
| Days to maturity | 90–165 from seed |
| How to start | Sow peanuts 1½ inches deep when soil is above 65°F, hill the plants and keep the soil evenly moist so pegs reach the ground |
| Water | 1.5 in per week |
These are the same numbers our plant spacing, square foot and harvest date calculators use. See every crop in the plant database.
When to plant peanut
Plant when soil is above 65°F, usually around the last frost. Days to maturity from USU: Valencia 120–130, Early Spanish 90–130, Early or Jumbo Virginia 120–130, runner types 125–165. Dig plants in fall when leaves begin to yellow or after the first frost. Use your frost dates to see if your season is long enough.
How to plant peanut
- Sow seeds about 1½ inches deep, 18 inches apart with 4 seeds per mound, in rows 24 inches apart. See the plant spacing calculator.
- Choose light, sandy, humus-rich soil. Most soils work if enough organic matter is added; USU suggests no more than 1 inch of compost per 100 square feet.
- Hill the plants. When plants are about a foot tall, mound 6 inches of soil around them so pegs can enter loose soil.
Caring for peanut
Provide 1 to 2 inches of water per week with uniform soil moisture; irregular watering, whether too much or too little, can cause root rot and lower yields. See the garden watering calculator.
Insects rarely affect peanuts, but wireworms, armyworms, cutworms, aphids, thrips and corn earworms may occur. Mice and other ground animals may eat developing or drying nuts, so exclusion measures may be needed. See the pest identifier.
Companion plants
| Grow nearby | Other warm-season crops in sandy, well-drained beds |
|---|---|
| Keep apart | Heavy clay and irregular watering |
Peanuts fix nitrogen like other legumes, but USU's page does not give rotation guidance, so rotate beds as you would with beans. Check other pairings with the companion plant finder.
Common problems
| Problem | What you see | What to do |
|---|---|---|
| Pods not forming | Plenty of flowers but no pods | Pegs must penetrate and be covered by loose soil. Hilling at about 1 foot tall helps. |
| Root rot and low yield | Wilting or poor pod set | Caused by irregular watering, too much or too little. |
| Animal damage | Missing or chewed nuts | Mice and ground animals may eat developing or drying nuts; use exclusion measures. |
Not sure what you are looking at? The plant problem identifier ranks likely causes from the symptoms you see.
When and how to harvest
Dig plants in fall when leaves begin to yellow or after the first frost, then check the soil around the pulled plants to collect all pods. To cure, leave plants in a ventilated area for 1 to 2 weeks, then remove the pods. Dry pods in a warm, low-humidity area (below 60–70% relative humidity) for 2 to 3 more weeks, for a total drying time of about 4 weeks. Store dried nuts at 35–40°F and 50–60% relative humidity.
Plan your peanut
- Plant spacing calculator: how many plants fit your bed
- Planting calendar: sowing and transplant dates for your frost dates
- Frost dates by ZIP code: your last spring and first fall frost
- Harvest date calculator: when your crop will be ready
Frequently asked questions
How far apart should I plant peanuts?
Space peanuts 18 inches apart in rows 24 inches apart. In a square foot garden, plant 1 per square foot.
How deep do I plant peanut seed?
Sow peanut seeds about 1½ inches deep, 18 inches apart.
How long do peanuts take to grow?
90 to 165 days depending on type: Early Spanish 90–130, Valencia 120–130, runner 125–165.
How much water do peanuts need?
About 1.5 inches of water a week, from rain and watering combined. 1 to 2 inches per week with uniform soil moisture; irregular watering can cause root rot.
When do I plant peanuts?
When soil is above 65°F, usually around the last frost.
Why are my peanuts not forming pods?
Pegs must reach and be covered by soil; hill 6 inches of soil around plants when they are about a foot tall.
How do I cure peanuts?
About 4 weeks total: 1 to 2 weeks in a ventilated area, then 2 to 3 more weeks of drying in a warm, low-humidity place.