How to Grow Ultra Basil

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Ultra Basil

Ocimum basilicum 'Ultra'

herb

Ultra basil is a compact, high-yielding cultivar of sweet basil bred for superior leaf production and intense flavor. It features densely packed, medium-sized leaves on a bushy plant that reaches only 12-18 inches tall, making it ideal for containers and small spaces. This variety is known for exceptional disease resistance and a long harvest season.

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Example Ultra Basil timeline · Pittsburgh, PA (Zone 6b)

  1. Plant Ultra Basil

    Around Apr 17

    Near Pittsburgh's average last spring frost.

  2. Tend & protect

    Late spring–summer

    Watering, feeding, and pest-watch reminders.

  3. Harvest Ultra Basil

    Around Jun 6

    ≈ 50 days after planting

Sample dates for Pittsburgh, PA. Sign up to get exact Ultra Basil dates for your own zip code.

Growing Conditions

☀️
Sun: Full sun, 6-8 hours daily minimum; tolerates partial shade but best with maximum light
💧
Water: Keep soil consistently moist but not waterlogged; water when top inch of soil feels dry. More frequent watering needed in containers and hot weather. Avoid wetting foliage to reduce disease risk.
📏
Spacing: 8 inches
📅
Days to maturity: 50-70 days from seed to first harvest
🌱
Planting depth: 0.25 inches; seeds should be surface-sown or barely covered as they need light to germinate

Soil

Type: Well-draining loamy soil rich in organic matter
pH: 6.0-7.0
Amendments:
Compost aged manure peat moss or coconut coir perlite for container growing

Growing Zones

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Thrives in zones 3-11 as an annual; treat as tender annual everywhere except warm tropical regions

2a 2b 3a 3b 4a 4b 5a 5b 6a 6b 7a 7b 8a 8b 9a 9b 10a 10b 11a 11b

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Growth Stages

1

Germination & Seedling

7-14 days germination, 2-3 weeks to thinning stage

Tiny seedlings emerge with two small cotyledons (seed leaves), followed by first true leaves. Plant remains very delicate and tiny.

Provide consistent warmth (70-75°F ideal), high humidity, and bright indirect light. Keep soil moist but not soggy. Thin seedlings to proper spacing once they have 2-3 true leaves.

2

Vegetative Growth

3-4 weeks

Plant develops multiple stems and leaf pairs rapidly. Bushy growth with increasingly dense foliage. Height increases to 6-12 inches without pinching.

Pinch off growing tip when plant has 6-8 leaves to encourage bushier growth and prevent early flowering. Maintain consistent moisture and full sun exposure. Side-dress with balanced fertilizer every 2-3 weeks.

3

Flowering Induction

Ongoing throughout season if not pinched

Plant reaches mature size (12-18 inches). Flower spikes begin forming at stem tips with small white, pink, or purple flowers clustered together.

Continue pinching flowers to extend leaf production and delay seed setting, which diverts energy from foliage. Ultra variety resists bolting better than standard basil but benefits from regular deadheading.

4

Leaf Harvest & Maintenance

6-12 weeks depending on climate and care

Plant is in peak production with full, dense foliage. Regular harvesting keeps plant vigorous and prevents it from becoming woody.

Harvest leaves regularly from top and sides to maintain bushiness. Never remove more than one-third of plant at once. Continue fertilizing and consistent watering. Remove any diseased or yellowing leaves immediately.

5

End of Season

1-4 weeks before frost kill

In fall or when temperatures drop below 50°F, plant growth slows significantly. Leaves may become smaller and less tender. Plant eventually dies in frost.

Harvest aggressively before first frost if possible. Can extend season by moving containers indoors to a sunny window. No frost tolerance—bring indoors or accept plant's death.

Companion Planting

Plan your garden →

Plant with:

Avoid planting near:

Rue Fennel Kohlrabi Mustard

Common Pests

  • Hand-pick in early morning; use neem oil spray; encourage predatory insects like parasitic wasps

  • Increase humidity by misting; spray with water to dislodge; use neem oil or miticide if severe

  • Use yellow sticky traps; spray with insecticidal soap or neem oil; remove heavily infested leaves

  • Remove damaged leaves; use blue sticky traps; spray with neem oil or spinosad

  • Ultra variety has improved resistance; ensure excellent drainage; remove affected plants; avoid overhead watering; rotate planting locations

Uses

🍳

Fresh Pesto & Sauces

Culinary

Ultra basil's intense, aromatic flavor and high leaf yield make it ideal for traditional Italian pesto, Thai green curry pastes, and fresh herb sauces. The compact growth habit provides abundant harvestable leaves throughout the season. [source]

🍳

Fresh Cooking & Flavoring

Culinary

Use fresh leaves to flavor pasta dishes, Caprese salads, soups, vinegars, oils, and beverages. Basil's volatile oils provide distinctive licorice-mint flavor best appreciated when raw or added at the end of cooking. [source]

💊

Herbal Tea & Digestive Aid

Medicinal

Brew fresh or dried basil leaves as a soothing tea to support digestion, reduce inflammation, and provide antioxidant benefits. Traditionally used in Ayurvedic and Mediterranean herbalism for its warming properties. [source]

🏠

Natural Aromatics & Pest Deterrent

Household

Dried basil retains strong fragrance for potpourri and sachets. Living basil plants naturally repel flies, mosquitoes, and other insects due to their volatile essential oils, making them useful near windows and sitting areas. [source]

🎨

Dried Herb & Culinary Garnish

Craft

Dry basil leaves by hanging stems or using a dehydrator to preserve for winter use. Dried basil concentrates flavors and stores well in airtight containers for months. [source]

This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.

Harvest Tips

Begin harvesting leaves once plant has 6-8 leaf pairs (about 4-5 weeks after planting). Pinch off leaf clusters from the top and sides regularly to encourage bushier growth. Harvest in the morning after dew dries for best flavor and aroma. Never remove more than one-third of the plant at once. The more you harvest, the more the plant produces—regular harvesting extends productivity. Pinch off flower buds to redirect energy to foliage production and maintain tender leaf texture.

Fun Facts

  • 🌱 Ultra basil was specifically bred by seed companies to resist Fusarium wilt, a common fungal disease that devastates standard basil varieties, making it more reliable for home gardeners.
  • 🌱 Basil is native to tropical regions of central Africa and Southeast Asia and was cultivated as a sacred plant in Hindu temples thousands of years ago.
  • 🌱 Unlike most herbs that become stronger-flavored when dried, basil's flavor diminishes significantly when dried due to loss of volatile aromatic oils, so fresh basil is always preferred for best flavor.

Gardening Terms

New to gardening? Learn about terms used in this guide:

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