Indiana gardeners achieve the best results by planting nasturtium in late April or early May. Knowing the best time to plant nasturtium in indiana is key to getting those bright blooms and edible leaves. This timing helps you avoid the last frost and gives seeds the warm soil they need.
Nasturtiums are easy to grow and add color to any garden. They also attract good bugs and keep pests away. Let’s walk through everything you need to know for planting success in the Hoosier state.
Best Time To Plant Nasturtium In Indiana
The short answer is late April to early May. But you need to check your local frost dates first. Indiana has three main growing zones: 5b, 6a, and 6b. The last frost can happen anywhere from mid-April to early May.
Soil temperature matters just as much as the calendar date. Nasturtium seeds germinate best when soil is between 55°F and 65°F. If you plant too early, seeds may rot in cold, wet ground.
Frost Date Guide For Indiana Regions
Northern Indiana (zones 5b-6a): Last frost usually around May 1-15. Plant in early May. Southern Indiana (zones 6a-6b): Last frost around April 15-30. Plant in late April. Central Indiana: Last frost around April 20-May 5. Plant in early May.
Always check your local extension service for exact dates. A quick online search for your county’s frost dates gives you a solid starting point.
Soil Temperature Check
Use a soil thermometer to be sure. Insert it 2 inches deep in the morning. If it reads 55°F or higher for three days in a row, you are good to go. This is more reliable than guessing by the weather.
If you don’t have a thermometer, watch for other signs. When dandelions bloom and soil crumbles easily in your hand, it is usually warm enough. Cold, clumpy soil means wait a bit longer.
How To Plant Nasturtium Seeds In Indiana Soil
Nasturtiums do best in poor to average soil. Rich soil makes them grow lots of leaves but few flowers. They like full sun but can handle some afternoon shade in hot Indiana summers.
Follow these steps for planting success:
- Choose a spot with well-draining soil and 6-8 hours of sun.
- Soak seeds in warm water for 12-24 hours before planting. This softens the hard seed coat and speeds up germination.
- Plant seeds 1 inch deep and 10-12 inches apart.
- Water gently after planting. Keep soil moist but not soggy.
- Watch for sprouts in 7-14 days.
Starting Seeds Indoors
You can start seeds indoors 4-6 weeks before the last frost. Use peat pots or biodegradable containers. Nasturtiums have delicate roots and don’t like being moved.
Plant 2 seeds per pot, 1 inch deep. Keep them in a warm spot with plenty of light. After the last frost, harden off seedlings by putting them outside for a few hours each day. Then transplant carefully without disturbing roots.
Direct Sowing In The Garden
Direct sowing is easier and often works better. Nasturtiums grow fast from seed and don’t need special care. Just wait until the soil warms up and plant them where you want them to grow.
For a continuous bloom, plant new seeds every 2-3 weeks until midsummer. This gives you flowers from June until the first fall frost. Indiana’s long growing season supports this method well.
Best Nasturtium Varieties For Indiana Gardens
Some varieties handle Indiana’s humidity and temperature swings better than others. Here are top picks:
- Alaska Mix: Variegated leaves, compact growth, good for borders.
- Jewel Mix: Dwarf plants, bright colors, great for containers.
- Empress of India: Deep red flowers, dark leaves, heat tolerant.
- Moonlight: Pale yellow blooms, climbing habit, good for trellises.
- Peach Melba: Soft peach flowers, bushy growth, unique color.
All these varieties grow well in Indiana’s climate. Choose based on your space and color preferences. Climbing types need a trellis or fence for support.
Caring For Nasturtiums Through Indiana Summers
Nasturtiums are low maintenance once established. They actually thrive on neglect. Too much water or fertilizer reduces blooms and encourages leaf growth.
Watering Tips
Water only when the top inch of soil feels dry. Overwatering leads to root rot and fewer flowers. In Indiana’s humid summers, morning watering is best. It lets leaves dry out during the day and prevents fungal diseases.
If you see yellowing leaves, you are probably watering too much. Cut back and let the soil dry out between waterings. Nasturtiums are drought tolerant once established.
Fertilizer Needs
Do not fertilize nasturtiums. They get all the nutrients they need from average garden soil. Extra fertilizer makes them grow big leaves but few flowers. If your soil is very poor, add a little compost at planting time.
If you must use fertilizer, choose a low-nitrogen option like 5-10-10. Apply sparingly once during the growing season. Too much nitrogen is the most common mistake Indiana gardeners make.
Pest And Disease Management
Nasturtiums attract aphids, which is actually a good thing. They act as trap plants, drawing aphids away from your vegetables. You can spray aphids off with a strong stream of water or leave them for beneficial insects.
Other common pests include caterpillars and slugs. Handpick caterpillars if you see them. Use beer traps or diatomaceous earth for slugs. Powdery mildew can appear in humid weather. Space plants well for air circulation and avoid overhead watering.
Using Nasturtiums In Indiana Landscapes
Nasturtiums are versatile plants that work in many garden settings. Their bright flowers and round leaves add instant charm. Here are some ways to use them:
- Edging along garden beds or walkways.
- Spilling over containers and window boxes.
- Climbing up trellises, fences, or arbors.
- Ground cover under taller plants.
- Companion planting near vegetables like tomatoes and cucumbers.
They also make great cut flowers. The blooms last about a week in a vase. Pick them in the morning when they are fully open for the longest vase life.
Harvesting Leaves And Flowers
Both leaves and flowers are edible. They have a peppery, radish-like flavor. Harvest leaves when they are young and tender. Older leaves can be tough and bitter.
Pick flowers just before using them. They wilt quickly after picking. Use them in salads, as garnishes, or infused in vinegar. The seeds can be pickled and used like capers.
Common Mistakes Indiana Gardeners Make
Even experienced gardeners sometimes get nasturtiums wrong. Here are the most common errors and how to avoid them:
- Planting too early in cold soil. Seeds rot instead of sprouting.
- Using rich soil or fertilizer. Too many leaves, not enough flowers.
- Overwatering. Leads to root rot and fungal issues.
- Planting in too much shade. Fewer blooms and leggy growth.
- Not soaking seeds before planting. Slower and uneven germination.
Avoid these mistakes and your nasturtiums will thrive. They are forgiving plants, but they do best when you follow their basic needs.
Extending The Bloom Season In Indiana
Nasturtiums bloom from early summer until the first fall frost. You can extend their season with a few simple tricks:
- Deadhead spent flowers regularly to encourage more blooms.
- Water during dry spells to keep plants healthy.
- Mulch around plants to keep soil cool and moist.
- Plant in containers that can be moved to sheltered spots in fall.
- Cover plants with row covers if an early frost is predicted.
With good care, you can enjoy nasturtiums from June through October in most parts of Indiana. The first hard frost usually ends the season, but you can bring containers indoors to extend it further.
Frequently Asked Questions
Can I Plant Nasturtium Seeds In July In Indiana?
Yes, but they may not bloom as long. Plant by mid-July for flowers before the first fall frost. Choose fast-growing varieties and keep them well watered during hot weather.
Do Nasturtiums Come Back Every Year In Indiana?
No, they are annuals in Indiana’s climate. They die with the first hard frost. But they often self-seed if you leave some flowers to go to seed. You may get new plants next spring without replanting.
How Long Do Nasturtium Seeds Take To Germinate?
Typically 7-14 days, depending on soil temperature. Soaking seeds overnight speeds up germination. Cool soil delays sprouting, so wait until the ground warms up.
Can I Grow Nasturtiums In Pots On My Patio?
Absolutely. Use pots at least 6 inches deep with drainage holes. Dwarf varieties work best for containers. Water more often since pots dry out faster than garden soil.
What Should I Do If My Nasturtiums Have Lots Of Leaves But No Flowers?
This usually means too much nitrogen or too much water. Stop fertilizing and let the soil dry out between waterings. Move plants to a sunnier spot if they are in shade. Blooms should appear within a few weeks.
Final Thoughts On Planting Nasturtium In Indiana
Timing is everything when planting nasturtiums in Indiana. Wait for warm soil and the last frost to pass. Late April to early May is the sweet spot for most of the state. With the right care, these cheerful flowers will brighten your garden all summer long.
Remember to soak seeds before planting, give them full sun and poor soil, and water sparingly. Avoid common mistakes like overwatering and fertilizing. Follow these tips and you will have a beautiful, low-maintenance display that even beginner gardeners can achieve.
Nasturtiums are one of the easiest flowers to grow in Indiana. They reward you with color, edible leaves, and natural pest control. Plant them at the right time and enjoy the results all season.