Learn About Salpiglossis

How to Sow

How to Sow and Plant

Salpiglossis may be grown from seed sown early indoors and transplanted outside after frost, or sown directly in the garden.

Sowing Seed Indoors:

  • Sow salpiglossis indoors 8 weeks before the last frost.
  • Sow seed ¼ inch deep in seed starting formula. Be sure to cover and keep away from the light until the seeds germinate, as salpiglossis needs darkness in order to germinate.
  • Keep the soil moist at 70-75 degrees F
  • Seedlings emerge in 14-30 days
  • As soon as seedlings emerge, provide plenty of light on a sunny windowsill or grow seedlings 3-4 inches beneath fluorescent plant lights turned on 16 hours per day, off for 8 hours at night. Raise the lights as the plants grow taller. Incandescent bulbs will not work for this process because they will get too hot. Most plants require a dark period to grow, do not leave lights on for 24 hours.
  • Seedlings do not need much fertilizer, feed when they are 3-4 weeks old using a starter solution (half strength of a complete indoor houseplant food) according to manufacturer’s directions.
  • If you are growing in small cells, you may need to transplant the seedlings to 3 or 4 inch pots when seedlings have at least 2 pairs of true leaves before transplanting to the garden so they have enough room to develop strong roots.
  • Before planting in the garden, seedling plants need to be “hardened off”. Accustom young plants to outdoor conditions by moving them to a sheltered place outside for a week. Be sure to protect them from wind and hot sun at first. If frost threatens at night, cover or bring containers indoors, then take them out again in the morning. This hardening off process toughens the plant’s cell structure and reduces transplant shock and scalding.

Sowing Directly in the Garden:

  • Direct sow in full sun in a rich, well-drained soil after danger of frost.
  • Remove weeds and work organic matter into the top 6-8 inches of soil; then level and smooth.
  • Sow seeds evenly and thinly in rows 18 inches apart and cover with ¼ inch of fine soil. Be sure to cover seed entirely as seed needs darkness in order to germinate.
  • Firm lightly and keep evenly moist.
  • Seedlings will emerge in 14-30 days depending on soil and weather conditions.
  • Thin to stand about 9-12 inches apart starting when seedlings are 1 inch high.

Transplanting in the Garden:

  • Select a location in full sun with a rich, well-drained soil.
  • 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.
  • The addition of organic matter (leaf mold, compost, well-rotted manure) benefits all gardens and is essential in recently constructed neighborhoods.
  • Space plants about 9-12 inches apart.
  • Thoroughly water and apply a light mulch layer on top of the soil (1-2 inches) to conserve water and reduce weeds.

How to Grow

  • Keep weeds under control during the growing season. Weeds compete with plants for water, space and nutrients, so control them by either cultivating often or use a mulch to prevent their seeds from germinating.
  • Mulches also help retain soil moisture and maintain even soil temperatures. For annuals an organic mulch of shredded leaves lends a natural look to the bed and will improve the soil as it breaks down in time. Always keep mulches off a plant’s stems to prevent possible rot.
  • Keep plants well-watered during the growing season, especially during dry spells. Plants need about 1 inch of rain per week during the growing season. Use a rain gauge to check to see if you need to add water. It's best to water with a drip or trickle system that delivers water at low pressure at the soil level. If you water with overhead sprinklers, water early in the day so the foliage has time to dry off before evening, to minimize disease problems. Keep the soil moist but not saturated.
  • After new growth appears, a light fertilizer may be applied. Keep granular fertilizers away from the plant crown and foliage to avoid burn injury. Use low rates of a slow release fertilizer, as higher rates may encourage root rots.
  • Remove spent flower spikes to encourage flowering and prevent seed development.
  • Pinch the growing tips of plants when they are about 4 inches tall to encourage bushiness.
  • Monitor for pests and diseases. Check with your local Cooperative Extension Service for pest controls recommended for your area.

Growing tips

  • Salpiglossis tends to prefer cooler growing conditions.
  • Salpiglossis can happily mingle with vegetables, and is a great cottage garden flower.
  • Salpiglossis makes a beautiful cut flower.
  • Regular deadheading promotes continuous bloom throughout the season.

Common Pests and Problems

Root Rots: A number of pathogens cause root rots of seedlings as well as mature roots. Burpee Recommends: Practice crop rotation and do not plant related crops in the same area for several years. Pull up and discard infected plants. Make sure your soil has excellent drainage. Contact your Cooperative Extension Service for recommendations.

Common Pest and Cultural Problems

Aphids: Greenish, red, black or peach colored sucking insects can spread disease as they feed on the undersides of leaves. They leave a sticky residue on foliage that attracts ants. Burpee Recommends: Introduce or attract natural predators into your garden such as lady beetles and wasps who feed on aphids. You can also wash them off with a strong spray, or use an insecticidal soap.

FAQ

Can I grow salpiglossis in a container? Yes, they are excellent container plants.

Why are my salpiglossis plants leggy? Salpiglossis needs full sun, at least six hours daily. They can be narrow plants and benefit from pinching when they are young to encourage bushiness. They sometimes need to be staked.

Does salpiglossis attract pollinators? Yes, salpiglossis attracts bees and butterflies to the garden.

My salpiglossis is not looking very good in my southern garden. What’s wrong? Salpiglossis performs best where nights are cool, in the 50s. It may just be too warm for this plant in your garden.

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