The herb peppermint (Mentha × piperita) is a hybrid between spearmint (Mentha spicata) and watermint (Mentha aquatica). This amazingly aromatic herb is one of the oldest herbs used for ritual, culinary, and medicinal purposes. Peppermint will thrive in full sun and in almost any type of soil. This marvelous herb can be enjoyed for its refreshing fragrance and taste with little effort.
Peppermint is a versatile and aromatic herb that adds a refreshing flavor and fragrance to many culinary dishes, beverages, and even beauty products. Homegrown peppermint has a more intense flavor and higher oil content compared to store-bought options. Luckily, it is relatively easy to grow peppermint yourself from seeds with a little time and effort. In this comprehensive guide, we will walk through the entire process of growing peppermint from seed, from choosing the right seeds and preparing for planting to transplanting, caring for, and harvesting your peppermint.
Overview of Growing Peppermint
Peppermint (Mentha x piperita) is a hybrid between spearmint and watermint. It is a hardy perennial herb that can be grown successfully in USDA Hardiness Zones 3-11 with full sun exposure or light shade. Peppermint thrives in moist, well-drained soil with a slightly acidic pH of 6.0-7.0.
When growing peppermint from seeds you can either start the seeds indoors or direct sow them outdoors. Indoor seed starting 6-8 weeks before the last expected frost date gives the seedlings time to grow into young plants that can be transplanted outside after the danger of frost has passed. Direct sowing can be done in spring after the soil has warmed up to at least 65°F.
Peppermint seeds usually germinate within 10-15 days when planted at the proper depth and given consistent moisture and temperatures of 65-75°F. The seeds are tiny and require light to germinate, so surface sowing and gentle pressing into the soil is recommended.
Once seedlings emerge they grow rapidly into mature peppermint plants that can be harvested in around 70-90 days. With its vigorous growing habit, peppermint grown in garden beds will need to be contained to prevent spreading. Growing in containers is often ideal. Proper spacing watering, fertilization, and pest control will keep your peppermint healthy and productive.
Choosing Peppermint Seeds
When selecting peppermint seeds to grow, look for non-GMO, heirloom seed varieties from reputable companies. Some good options include:
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Organic peppermint seeds – Untreated, non-GMO heirloom seeds grown organically without pesticides.
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Standard peppermint seeds – Non-GMO, untreated conventional seeds. More affordable but not organic.
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Seed collections – Kits with a few varieties of mint like peppermint, spearmint, orange mint, etc. Fun way to grow different types.
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Named cultivars – Specific peppermint varieties like chocolate mint, lavender mint, or variegated mint.
Ensure the seed packets are properly labeled and within their expiration date. For best germination rates, use fresh seeds meant for the current growing season.
Starting Peppermint Seeds Indoors
Starting peppermint seeds indoors allows you to get a head start on the growing season. Here are some tips:
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Use seed starting mix – Use a lightweight, nutrient-rich soilless mix that drains well. Mix in vermiculite for added drainage.
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Start seeds 6-8 weeks before last frost – This gives enough time for seedlings to mature before moving them outside.
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Sow seeds shallowly – Peppermint seeds need light to germinate. Gently press seeds onto the soil surface and cover with a thin layer of vermiculite.
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Keep warm – Maintain a temperature of 65-75°F for fastest germination. Consider using a heat mat.
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Keep moist – Water gently when the top inch of soil dries out. Use a spray bottle to avoid dislodging seeds.
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Provide light – Place under grow lights or in a sunny window after germination.
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Transplant after 2-4 weeks – Transplant into cell packs or 3-4” pots once seedlings have 2-3 sets of leaves.
Direct Sowing Peppermint Outdoors
Peppermint can also be directly sown into the garden after the danger of frost has passed. Follow these tips:
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Prepare soil – Loosen soil and remove weeds/debris. Mix in compost. Peppermint likes enriched, well-drained soil.
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Test soil pH – Target slightly acidic pH of 6.0-7.0. Lime or sulfur can adjust pH if needed.
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Wait until soil warms up – 65-70°F soil temperature is ideal. Or sow 2-3 weeks after last spring frost.
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Sow 1⁄4 inch deep – Gently tamp seeds into moistened, cultivated soil. Space 1-2 inches apart in rows 18-24 inches apart.
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Keep soil moist – Water gently daily until seedlings emerge. Use a fine mist to avoid washing away seeds.
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Control weeds – Weed gently by hand once seedlings emerge. Mulch to smother weeds.
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Thin seedlings – For proper air circulation and growth, thin to 12-18 inches apart once 2-4 true leaves appear.
Caring for Peppermint
Proper care is vital for peppermint to thrive after transplanting or direct sowing. Here are some growing tips:
Watering
- Maintain even moisture in top few inches of soil
- Avoid letting soil dry out completely
- Prevent soggy, waterlogged soil
- Increase watering in intense heat
Sunlight
- Grow in full sun to partial shade
- At least 6 hours of direct sun daily
- Light shade protects leaves in hot climates
Soil
- Peppermint likes rich, fertile, well-draining loamy soil
- Mix in compost or manure before planting
- Mulch to retain moisture and reduce weeds
Fertilizer
- Use all-purpose organic fertilizer once every 4-6 weeks
- Avoid over-fertilizing which can reduce flavor
- Foliar sprays like compost tea provide micronutrients
Pruning
- Prune flower stems to promote leaf growth
- Remove dead or damaged growth
- Cut back 1/3 of plant at a time to prevent stress
Pest control
- Watch for aphids, spider mites, mint rust
- Remove pests by hand or use natural insecticidal soap
- Improve air circulation and avoid wet foliage
Harvesting Peppermint
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Begin harvesting peppermint leaves once the plant reaches 4-6 inches tall.
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For the best flavor, harvest in the morning after the dew has dried but before the heat of the day.
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Cut stems 1-2 inches from the top. Use scissors or pruning shears for clean cuts.
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Avoid cutting more than 1/3 of the plant at a time to keep it healthy.
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Harvest leaves as needed throughout the growing season. Frequent pruning promotes bushy new growth.
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Harvest just before flowers appear in mid-summer for peak oil content and flavor.
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Dry leaves quickly in a warm, dark place or use fresh. Store dried leaves in airtight containers.
Growing Peppermint in Containers
Since peppermint spreads aggressively, contained growing is recommended to control its invasive nature. Follow these tips for growing peppermint in pots:
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Choose large containers at least 12-24 inches wide and deep. This allows room for root growth.
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Use containers with drainage holes and drainage trays to prevent soggy soil.
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Opt for quality potting mix with coconut coir or compost for moisture retention.
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Sink pots in the ground or place inside larger containers to help restrict roots.
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Water when the top 1-2 inches of soil become dry. Don’t let pots completely dry out.
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Apply organic granular fertilizer at half strength every 4-6 weeks during growing season.
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Prune frequently to control size and promote bushiness. Pinch off flower buds.
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Bring containers indoors before first fall frost. Peppermint can overwinter indoors near a sunny window.
Troubleshooting Common Problems
Growing peppermint from seed is relatively easy but sometimes issues can arise. Here are some common problems and solutions:
Seeds not germinating – Old/expired seeds, improper planting depth, insufficient moisture, or cool temperatures could be the culprit. Resow fresh seeds properly.
Leggy growth – Insufficient sunlight, over-fertilization, and inadequate pinching back can cause stretchy, weak growth. Improve light exposure, reduce fertilizer, and prune more frequently.
Wilting leaves – This can indicate underwatering, drought stress, root rot from overwatering, or disease. Improve watering practices and treat disease if present.
Leaf spots/discoloration – Leaf spots and yellowing often indicate disease like verticillium wilt, mint rust, or root rot. Improve air circulation and treat disease.
Pests – Aphids, spider mites, and other pests can be managed by hosing down plants, using insecticidal soap, and attracting beneficial insects.
Mint not spreading – When contained, mint grown from seed may not spread as aggressively at first. But over time, it will produce rhizomes and spread rapidly.
When grown properly from seed, homegrown peppermint provides you with an abundant supply of flavorful leaves perfect for teas, cocktails, desserts, and more. Follow this guide for step-by-step instructions from seed starting to troubleshooting. With patience and attentive care throughout the growing process, you’ll have delicious peppermint leaves to enjoy fresh from your own garden.
Pruning
Left unpruned, the peppermint plant can grow too aggressively, even in containers. Young leaves will be more flavorful than old faded leaves, so pruning these off will promote the emergence of new ones quickly and direct the plants energy there. The best place to trim is just above a leaf node. Keep in mind not to trim back more than a third of the plant. This could cause stress. Once your mint plant is mature, a weekly trimming to keep it neat and productive should be sufficient.
Harvesting
The ideal time to harvest peppermint is towards the middle of the growing season, just before flowers appear, but really, any time after the plant reaches 4 inches in height is ok. Harvest it in the morning for the highest concentration of the oil resulting in more intensity of the aroma and flavor. Cut stems back to about an inch above the soil or snip 2 to 3 inches from the very top. The stems will replenish and you will have more to harvest as the season goes.
How to Grow Peppermint From Seed / How to Prune Back / DMGV
FAQ
How long does it take to grow peppermint from seed?
Indoors and out, expect germination in 15-30 days. When sowing seed outdoors, we recommend a maximum planting depth of 4X the width of the seed.
Does peppermint come back each year?
Wintering Over — Peppermint is a perennial and will return year after year. Keeping it pruned and shaped will help it grow into a thick, bush-like plant. When it reaches 8 to 10 inches tall, cut it back by half its height each month of the growing season.
Is peppermint easy to grow?
Peppermint is fairly easy to grow as an herb so long as it has adequate moisture and nutrient rich soil. In ideal conditions, mint will grow quickly, sending out runners that will creep around and spread. Peppermint will also grow OK in dryer conditions with poor soil, but won’t be quite as productive.
Can Peppermint grow from seed?
Planting is the process of transferring the germinated seeds or seedlings to their final growing location. Peppermint plants can grow in pots or garden beds, as long as they have enough space, soil, water, and sun. The third step to growing peppermint from seed is to care for the plants.
When can I plant Peppermint seeds?
Peppermint is a very hardy plant, so late spring is not the only time you can plant. Peppermint can be grown anytime between the last frost of spring and 2 months before the first frost of fall. Rather than planting the seeds outside, you can also begin growing the seeds inside.
How do you plant Peppermint seeds?
To start, go to Amazon and get yourself a seed starter tray, and fill it with a quality seedling mix. When planting your seeds make sure to space them 3 – 4″ apart. Next, get your Peppermint seeds and press them into the loose soil about 1/4″ deep. Then you want to lightly cover the seeds with soil.
Can you grow Peppermint yourself?
Now let’s look at how to harness peppermint’s benefits by growing it yourself. When to plant: You can start peppermint seeds indoors 6-8 weeks before your last expected spring frost. Or, sow seeds directly in the garden after all danger of frost has passed. Peppermint can also be planted in fall in warm regions.
How long does it take Peppermint seeds to germinate?
Germination of Peppermint Seeds Peppermint seeds typically take 10-20 days to germinate. Humidity: To retain moisture and promote germination, cover the seed trays with clear plastic or a humidity dome. Light: Once the seeds begin to sprout, move them to a bright spot with indirect sunlight, or use grow lights if needed.
Can you plant Peppermint seeds outside?
Transplanting seedlings outdoors After hardening the seedlings, we transplant them outdoors into a large pot. Always grow peppermint in a pot, as the herb likes to spread and tends to take over. If you plant in your herb garden, it is a good idea to plant the seedling in a bucket or pot without a bottom.