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Stop in and “borrow” any seeds you like. After your plants have bloomed, save some of those seeds and bring them in to add to the seed collection!
The Marengo-Union Library District Seed Library contains a selection of vegetable, herb and flower seeds. Our selection changes throughout the year based on available donations.
Growing Guides
University of Illinois Extension:
- When to plant in Illinois?
- Herb Gardening Growing Guides
- Vegetable Gardening Growing Guides
- Fruit Gardening Growing Guides
- Flower Gardening Growing Guides
- Gardeners Corner
Cornell University:
NC State Extension:
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Plant Growing Tips
Click on a plant name for growing information. Please note: Our selection changes throughout the year based on available donations.
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Cosmos – Bright Lights
Growing Guides & Sources:
Seed starting indoors: Mar. 20 – Apr. 03
Plant outdoors: May 15 – May 29
Soil Temp: 70°F-75°F
Sunlight: Full Sun
Moisture Needs: Medium moist, Well drained
Sow: Seed start indoors 4-6 weeks before last frost
Seed Spacing: 5″-6″
Seed Depth: ¼”
Seedlings in 5-10 days
Plant height: 10″-24″
Bloom size: 2″-3″
Lifecycle: Annual
Tips:
- Prepare the bed by turning the soil under to a depth of 8 inches.
- When 1″ – 2″ tall, thin to 1 every 10″
- Remove plants after they are killed by heavy frost in fall
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Seed starting indoors: Feb. 06 – Mar. 06
Plant outdoors: Apr. 03 – May 15
Soil Temp: 70°F-75°F
Sunlight: Full Sun
Moisture Needs: Light moisture
Sow: Seed start indoors 10 weeks before last frost
Seed Spacing: 9″-12″
Seed Depth: ⅛”
Seedlings in 6-14 days
Plant height: 24″
Bloom size: 2″-3½”
Lifecycle: Annual
Tips:
- Prepare the bed by turning the soil under to a depth of 6″.
- When 1″- 2″ tall, thin to 1 every 8″ – 12″
- Remove plants after they are killed by heavy frost in fall
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Seed starting indoors: Feb. 20 – Mar. 06
Plant outdoors: Apr. 03 – May 01
Soil Temp: 60°F-65°F
Sunlight: Full Sun or Partial Shade
Moisture Needs: Moist, Well drained
Sow: Seed start indoors 8-10 weeks before last frost
Seed Spacing: 10″-24″
Seed Depth: ¹⁄₁₆”
Seedlings in 15-20 days
Plant height: 3′-5′
Bloom size: 2″-3″
Lifecycle: Perennial
Tips:
- Prepare the bed by turning the soil under to a depth of 6″-12″.
- When 2″ tall, thin to 1 every 18″-24″
- The plants, seeds, and foliage of this variety are all poisonous—please use caution.
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Morning Glory – Shiva
Growing Guides & Sources:
Plant outdoors: May 15 – May 29
Soil Temp: Above 55°F at night
Sunlight: Full Sun
Moisture Needs: Medium moist, Well drained
Sow: Directly in soil
Seed Spacing: 6″-12″
Seed Depth: ½”
Seedlings in 7-14 Days
Plant height: 8′-15′ vines
Bloom size: 2″
Lifecycle: Annual
Tips:
- Thin plants to stand 12″ apart when plants are 1″ to 2″ high.
- Morning glory is a vigorous vine; choose a location next to a support for the vines to climb.
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Purple Coneflower
Growing Guides & Sources:
Seed starting indoors: Feb. 06 – Mar. 06
Plant outdoors: Apr. 03 – May 15
Soil Temp: 65°F-70°F
Sunlight: Sun/Partial Shade
Moisture Needs: Medium moist, Well drained
Sow: Seed start indoors 10 weeks before last frost
Seed Spacing: 8”-10″
Row Spacing: 3′-4′
Seed Depth: ¼”
Seedlings in 10-20 days
Plant height: 3′-4′
Bloom size: 4″-6″
Lifecycle: Perennial
Tips:
- Seeds can be soaked in warm water for 24 hours before planting.
- Prepare the bed by turning the soil under to a depth of 6-12, inches removing any debris, and lightly raking as level as possible.
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Plant outdoors: Apr. 01 – May 15
Soil Temp: 65°F-75°F
Sunlight: Full Sun
Moisture Needs: Medium moist, Well drained
Sow: Grow in a container as a houseplant or directly in garden.
Seed Spacing: 12″
Seed Depth: ⅛”
Seedlings in 21-30 Days
Plant height: 8″-10″
Bloom size: 2″
Lifecycle: Annual
Tips:
- Soak the seeds in hot tap water for 20 minutes before sowing.
- Best watered at ground level to avoid “tripping” the leaves.
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Zinnia – Giant Cactus Mix
Growing Guides & Sources:
Seed starting indoors: Mar. 06 – Mar. 20
Plant outdoors: May 15 – May 29
Soil Temp: 70°F-75°F
Sunlight: Full Sun
Moisture Needs: Moist, Well drained
Sow: Seed start indoors 4-6 weeks before last frost
Seed Spacing: 12″
Seed Depth: ¼”
Seedlings in 7-10 days
Plant height: 2′-3′
Bloom size: 5″-6″
Lifecycle: Annual
Tips:
- Before planting in the garden, seedling plants need to be “hardened off”. Learn more.
- Prepare the bed by turning the soil under to a depth of 6″-8″.
- When 2″ tall, thin to 1 every 12″