Sesame: Indoor or Direct Sow Herb
How to Sow and Plant
Sesame may be grown from seed sown early indoors and transplanted outside after frost, or sown directly in the garden.
Sowing Seed Indoors:
- Sow sesame seeds indoors 4-6 weeks before the last frost in spring using a seed starting kit.
- Sow seeds ¼ inch deep in seed-starting formula.
- Keep the soil moist at 70 degrees F, sesame benefits from bottom heat.
- Seedlings emerge in 7-14 days.
- As soon as seedlings emerge, provide plenty of light on a sunny windowsill or grow seedlings 3-4 inches beneath 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 liquid 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 3 pairs of 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:
- Sesame plants need a well-drained soil.
- Direct sow in average soil in full sun after all danger of frost when the soil is at least 60 degrees F.
- Remove weeds and work organic matter into the top 6-8 inches of soil; then level and smooth.
- Sow seeds 6 inches apart and cover with ¼ inch of fine soil.
- Firm the soil lightly and keep evenly moist.
- Seedlings will emerge in 7-14 days, possibly longer in cooler soils.
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 herbs, an organic mulch of aged bark or 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.
- Monitor for pests and diseases.
Harvest and Preserving Tips
- Pods may be left on the plant until they are dried and the top of the pods have opened. Carefully harvest pods and pour seeds into a bowl.
- All pods must be harvested before the first frost. If the pods are not mature at that time, remove them and place them on newspapers to dry. When the pods are completely dried and have turned brown, crack them gently to remove the seeds.
- Make sure all the chaff is removed and store seeds when completely dry in an air tight jar.
Common Disease Problems
Alternaria Leaf Spot: Small, round reddish brown spots with white to grey centers form on the upper surface of the leaves and along the midrib. The lesions may encircle the stems and cause wilt. This disease is worse in warm, wet or very humid weather. Burpee Recommends: Avoid getting water on the foliage. Remove infected plant parts and do not work around wet plants. Provide plenty of air circulation. Contact your Cooperative Extension Service for fungicide recommendations.
Fusarium Wilt: This soil borne disease causes stunted and wilted plants and yellowish leaves. Brown streaks may occur on the stems and later signs of the disease are twisted stems and leaf drop. The stem tissue is discolored. Burpee Recommends: Remove and destroy plants. The disease is worse in poorly drained soil.
Leaf Blights: This causes tan spotting on the foliage and causes plants to lose vigor. Burpee Recommends: Rotate crops. Check with your Cooperative Extension Service for fungicide recommendations.
Powdery Mildew: This fungus disease occurs on the top of the leaves in humid weather conditions. The leaves appear to have a whitish or greyish surface and may curl. Burpee Recommends: Avoid powdery mildew by providing good air circulation for the plants by good spacing and pruning. Contact your Cooperative Extension Service for fungicide recommendations.
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 and a black sooty mold. 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.
Cutworms: These insects cut off seedlings at the soil level. Burpee Recommends: Place a paper cup collar (use a coffee cup with the bottom cut out) around the base of the plant. They are usually mostly a problem with young seedlings. You can also control by handpicking and controlling weeds, where they lay their eggs.
Gall Midges: Adults are tiny flies usually with long antennae resembling a fruit fly. Larvae are tiny yellow to orange maggots that can be found inside the galls feeding on the plant. Galls are distortions or lumps of plant tissue on plant leaves or stems. Burpee recommends: Removing infected leaves from the garden. If there are a lot of galls on the plant, remove and destroy the infected plant.
Spider Mites: These tiny spider-like pests are about the size of a grain of pepper. They may be red, black, brown or yellow. They suck on the plant juices removing chlorophyll and injecting toxins which cause white dots on the foliage. There is often webbing visible on the plant. They cause the foliage to turn yellow and become dry and stippled. They multiply quickly and thrive in dry conditions. Burpee Recommends: Spider mites may be controlled with a forceful spray of water every other day. Try hot pepper wax or insecticidal soap. Check with your Cooperative Extension Service for miticide recommendations.
Whitefly: These are small white flying insects that often rise up in a cloud when plants are disturbed or brushed against. Burpee Recommends: They are difficult to control without chemicals. Try hot pepper wax or insecticidal soap. Check with your Cooperative Extension Service for pesticide recommendations.
Sesame FAQs
My sesame seedling is not growing very fast is there something wrong? No, sesame plants are slow to start, especially if the soil is cool. They will grow faster once the soil warms up.
Is sesame self-pollinating? Yes, sesame is self-pollinating.
What is the scientific name of sesame? Sesamum indicum.
What color are sesame flowers? Sesame has pink flowers and is quite ornamental.
Can I grow sesame in a container? We do not recommend growing sesame in containers because the plants grow quite large.