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Basil 'Dark Opal'     

Ocimum basilicum

  • 63 plantings
  • 12 available for swap
  • 8 wanted
  • 57 stashed

Belonging to the Ocimum genus (Ocimum basilicum 'Dark Opal'), Dark Opal is a variety of Basil. Dark Opal is generally thought of as a open-polliated variety. Blooms appear in these approximate colours:   Lavender purple and   Purple Heart. Leaves appear approximately as a   Tyrian purple and   Dark olive green colour. A type of Herb, it mainly grows as an Annual plant - which means it typically only grows best for a single growing season. Dark Opal is known for growing with a forb-like habit to a height of approximately 45.0 cm (that's 1.46 feet in imperial).

India is believed to be where Dark Opal originates from.

Being a fairly low maintenance plant, Dark Opal Basil is normally quite easy to grow provided a minimum level of care is given throughout the year. It will be helpful to note the correct soil, sun and water needs of this plant to ensure that this plant thrives.

This variety plant info is provided by the myfolia gardener's wiki. All details about Dark Opal have been kindly provided by our members.

How to grow Dark Opal

  • Full Sun

  • Medium

Pinch terminal shoots to encourage branching.
Harvest leaves before flowering occurs, or they will be bitter.

Dark Opal likes a position of full sun and remember to water moderately. Keep in mind when planting that Dark Opal is thought of as half hardy, so although it can survive a small mild cold snap, it is wise to ensure that this plant is protected from frost damage. Use USDA Hardiness Zone 4 - 11 as your guideline for the appropriate climate for this plant. Planting Dark Opal in loamy, sandy and silty soil with a ph of between 6.0 and 7.5 is ideal for as it does best in weakly acidic soil to weakly alkaline soil.

Growing Dark Opal from seed

Cover with finely sieved compost.

Sow 0.12 inches (0.3 cm) deep with a guideline distance of 0.5 inches (1.27 cm). Soil temperature should be kept higher than 10°C / 50°F to ensure good germination.

By our calculations, you should look at sowing Dark Opal about 20 days before your last frost date.

Transplanting Dark Opal

Plant out when frost risk has passed.

As Dark Opal is half hardy, ensure temperatures are mild enough to plant out - wait until after your last frost date to be on the safe side.

By our calculations, you should look at planting out Dark Opal about 21 days after your last frost date.

Harvesting Dark Opal

This variety tends to be ready for harvesting by mid summer.

Basil Dark Opal Etymology

The word basil means “king” in Greek – it is believed to have grown above the spot where St. Constantine and Helen discovered the Holy Cross.

Dark Opal folklore & trivia

Jewish folklore says that basil adds strength while fasting.

Misspellings of Basil 'Dark Opal'

Dark Opal Purple

Latest Basil 'Dark Opal' Reviews

  • Very easy and a very tasty plant that is great for beginners and pros alike. My garden would not be the same with out it.

    5 stars

    dragonloverlord about growing Purple Basil

See all Dark Opal reviews and experiences »

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