How to Grow Roundup Ready Soybean P1535AM

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Roundup Ready Soybean P1535AM

Glycine max

vegetable

P1535AM is a genetically modified soybean cultivar engineered to tolerate glyphosate herbicide applications, enabling broad-spectrum weed control. This early-maturity variety (Maturity Group 1.5) is designed for northern growing regions and produces high yields of oil-rich beans suitable for feed, food processing, and biodiesel production.

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Example Roundup Ready Soybean P1535AM timeline · Pittsburgh, PA (Zone 6b)

  1. Plant Roundup Ready Soybean P1535AM

    Around Apr 17

    Near Pittsburgh's average last spring frost.

  2. Tend & protect

    Late spring–summer

    Watering, feeding, and pest-watch reminders.

  3. Harvest Roundup Ready Soybean P1535AM

    Around Jul 26

    ≈ 100 days after planting

Sample dates for Pittsburgh, PA. Sign up to get exact Roundup Ready Soybean P1535AM dates for your own zip code.

Growing Conditions

☀️
Sun: Full sun, 6-8 hours minimum daily (prefers 8+ hours for optimal pod set)
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Water: Consistent moisture during germination and pod-filling stages; 1.5-2.0 inches per week via rainfall or irrigation. Reduce watering after pod set to encourage maturation.
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Spacing: 6-8 inches between plants in rows 30 inches apart for commercial production; home gardeners may use 12-18 inch spacing inches
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Days to maturity: 100-115 days (MG 1.5 classification)
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Planting depth: 1-1.5 inches deep; plant when soil temperature reaches 60°F (ideally 65-70°F)

Soil

Type: Well-draining loamy to clay loam soil
pH: 6.0-7.0
Amendments:
Nitrogen-fixing bacteria inoculant (Bradyrhizobium japonicum) Phosphorus and potassium if soil tests show deficiency Organic matter or compost for improved water retention

Growing Zones

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Zones 3-6; excellent for northern US and Canada due to early maturity and shorter growing season requirement

3a 3b 4a 4b 5a 5b 6a 6b

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Growth Stages

1

Germination & Emergence

7-14 days

Seeds absorb moisture and germinate underground; cotyledons (seed leaves) emerge above soil within 7-10 days

Ensure soil moisture is consistent but not waterlogged to prevent damping-off. Maintain soil temperature above 60°F. Thin seedlings if crowded.

2

Vegetative Growth

30-40 days

Plant develops true leaves in a trifoliolate pattern; begins rapid stem and leaf expansion; nitrogen fixation by nodules becomes active

Monitor for early weeds and aphids. Apply glyphosate herbicide (Roundup) as needed since this variety tolerates it. Ensure adequate moisture but avoid waterlogging.

3

Flowering

15-20 days

Small white, pink, or purple flowers appear in leaf axils; plant reaches maximum vegetative height; flower clusters develop along stem

Critical stage for avoiding stress; maintain consistent water supply (1.5-2.0 inches per week). Reduce nitrogen fertilizer. Monitor for spider mites and pod borers.

4

Pod Development & Filling

20-25 days

Flowers develop into pods containing 1-3 seeds; pods enlarge and seeds grow; leaf yellowing begins

Continue irrigation through early seed fill; reduce water slightly as maturity approaches. Avoid late-season nitrogen applications. Watch for pod-feeding insects.

5

Maturity & Harvest Ready

10-15 days

Pods dry and brown; leaves yellow and drop; seeds rattle in pods when shaken; plant reaches full maturity

Stop irrigation 2-3 weeks before harvest to allow dry-down. Allow field to dry naturally until pods crack when squeezed. Harvest when moisture content drops to 12-15%.

Companion Planting

Plan your garden →

Plant with:

Corn (in rotation; not simultaneous planting) Clover (as cover crop or rotation) Oats (as cover crop) Winter wheat (in rotation)

Avoid planting near:

Other soybean varieties (cross-pollination not an issue, but disease pressure increases) Sunflower (allelopathic competition) Fields with known herbicide-resistant weeds (unless management strategy is confirmed)

Common Pests

  • Monitor populations weekly; spray insecticide if >250 aphids per plant; encourage natural predators like ladybugs

  • Hand-pick if populations are low; apply neem oil or pyrethrin-based insecticide; encourage cultural controls

  • Increase irrigation to reduce heat stress; spray with miticide if leaves show stippling; release predatory mites

  • Early detection and removal; apply insecticide at pod formation if threshold (1 beetle per plant) is exceeded

  • Use resistant varieties; rotate crops; practice extended rotations away from soybeans; soil fumigation in severe cases

  • Apply fungicide at first sign of lesions; choose disease-resistant varieties; improve air circulation

Uses

🍳

Animal Feed & Protein Source

Culinary

P1535AM soybeans are processed into high-protein meal for livestock feed and aquaculture. The seeds are rich in protein (36-40%) and used in poultry, swine, and cattle rations. [source]

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Edible Oil Production

Culinary

Seeds contain 18-22% oil, which is extracted for cooking oil, margarine, and food additives. Soybean oil is one of the world's most widely used vegetable oils. [source]

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Biodiesel & Biofuel

Household

Soybean oil can be processed into biodiesel fuel for diesel engines, reducing petroleum dependence. One bushel of soybeans yields approximately 1.5 gallons of biodiesel. [source]

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Isoflavones & Plant Compounds

Medicinal

Soybeans contain isoflavones (genistein, daidzein) studied for potential health benefits including bone health and hormonal support in food supplements. [source]

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Industrial Products

Household

Soybean-derived compounds are used in adhesives, plastics, inks, and lubricants as sustainable alternatives to petroleum-based products. [source]

This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.

Harvest Tips

Harvest when pods are brown and dry (typically late August to October depending on planting date and zone). Pods should rattle when shaken. Target seed moisture of 12-15% for combining; allow field to cure naturally if possible. Use a combine harvester for commercial-scale production, cutting at pod height. For small-scale harvest, pull plants and thresh by hand or mechanical thresher.

Fun Facts

  • 🌱 Roundup Ready soybeans (introduced by Monsanto in 1996) revolutionized weed management by allowing farmers to spray glyphosate herbicide over the entire crop without damaging the plants, dramatically reducing tillage and soil erosion.
  • 🌱 P1535AM's Maturity Group 1.5 rating means it requires approximately 1,500 Growing Degree Days (base 50°F) to mature, making it one of the earliest-maturing groups suitable for northern regions with shorter growing seasons.
  • 🌱 Soybeans are nitrogen-fixing legumes that form symbiotic relationships with Bradyrhizobium bacteria in soil; a healthy soybean crop can add 100-200 lbs of nitrogen per acre back into the soil, reducing fertilizer needs for subsequent crops.

Gardening Terms

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