How to Grow Zinnia Oklahoma Purple

Zinnia Oklahoma Purple

Zinnia Oklahoma Purple

Zinnia elegans 'Oklahoma Purple'

flower

Oklahoma Purple is a compact, bushy zinnia cultivar renowned for its rich, deep purple double flowers and exceptional disease resistance. This variety grows to moderate heights and produces abundant blooms throughout the growing season, making it an excellent choice for borders, containers, and cut flower arrangements. It is particularly valued for its vigor and reliability in various growing conditions.

Growing Conditions

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Sun: Full sun, 6-8 hours daily minimum; 8+ hours preferred for best flowering and disease resistance
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Water: Moderate watering; allow soil to dry slightly between waterings. Water at soil level to keep foliage dry and reduce disease. Once established, fairly drought-tolerant but performs best with consistent moisture during bloom season.
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Spacing: 12 inches
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Days to maturity: 50-65 days to first flowers
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Planting depth: 1/4 inch; seeds should be surface-sown or barely covered as they need light to germinate

Soil

Type: Well-draining loamy to sandy soil
pH: 6.0-7.0
Amendments:
Compost Peat moss or coconut coir Perlite or coarse sand for drainage Balanced slow-release fertilizer

Growing Zones

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Thrives in zones 3-11 as an annual; prefers warm conditions and blooms prolifically in zones 5-10

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Growth Stages

1

Seed/Germination

7-10 days

Tiny seeds are sown on or just under soil surface. Seedlings emerge within 7-10 days with characteristic cotyledons.

Keep soil consistently moist but not waterlogged. Maintain 70-75°F for optimal germination. Provide bright light once sprouted.

2

Seedling

2-3 weeks

Young plants develop their first true leaves and establish a small root system. Growth is relatively rapid.

Thin to appropriate spacing or transplant into individual cells. Provide bright, indirect light. Begin dilute fertilization once true leaves appear.

3

Vegetative/Growth

3-4 weeks

Plants develop into bushy, leafy specimens with increasingly sturdy stems. Height reaches 12-18 inches depending on conditions.

Pinch back growing tips at 4-6 inches to encourage branching and compact growth. Water consistently. Apply balanced fertilizer every 2-3 weeks. Ensure excellent air circulation.

4

Flowering

6-10 weeks (often until frost)

Abundant double purple flowers appear at branch terminals. Blooms are full, pompom-like, and deepest purple in cooler conditions.

Deadhead spent flowers regularly to encourage continuous blooming. Water at soil level to prevent powdery mildew. Switch to balanced or higher phosphorus fertilizer weekly.

5

Late Season/Senescence

Until first frost

Plants continue flowering until frost. As temperatures drop, blooms may deepen in color. Production gradually slows.

Continue deadheading if desired. Allow some flowers to mature if saving seed. Frost will kill the plant; pull up and compost.

Common Pests

  • Ensure good air circulation; mist foliage with water regularly; use insecticidal soap or neem oil if infestation occurs; avoid overhead watering

  • Water at soil level only; ensure excellent air circulation; remove affected leaves; apply sulfur or baking soda spray (1 tbsp baking soda + 1 tbsp horticultural oil per gallon water); avoid dense planting; Oklahoma Purple has excellent natural resistance

  • Use yellow sticky traps; spray with insecticidal soap; encourage natural predators; use reflective mulches

  • Remove affected flowers; use blue or yellow sticky traps; spray with insecticidal soap or neem oil; encourage beneficial insects

  • and

    Remove debris and dense ground cover; use copper tape barriers; hand-pick at dusk; set beer traps; apply diatomaceous earth around base

Uses

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Edible flowers for garnish

Culinary

Zinnia petals are edible and provide a beautiful, mild flavor for salads, desserts, and cocktails. The purple color makes them particularly striking as a garnish for upscale dishes. [source]

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Cut flower arrangements

Household

Oklahoma Purple zinnias are exceptional long-lasting cut flowers, remaining fresh in a vase for up to 2-3 weeks. Their full double blooms and rich color make them centerpieces or floral design staples. [source]

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Pollinator attraction

Wildlife

Despite their double-flower form, Oklahoma Purple zinnias attract butterflies, bees, and hoverflies, providing valuable nectar and pollen sources throughout the growing season. [source]

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Dried flowers

Craft

The sturdy double flowers dry exceptionally well, retaining their purple color and form for dried arrangements, wreaths, and craft projects. Hang-dry upside down in a warm, dark location. [source]

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Traditional herbal use

Medicinal

Zinnias have been used in traditional medicine for their purported anti-inflammatory and antioxidant properties. Petals can be dried for herbal tea, though scientific evidence is limited. [source]

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

Harvest Tips

Cut flowers in early morning after dew dries but before heat of day. Use sharp scissors or pruners to cut stems just above a leaf node or branch point. Cut flowers are longest-lasting if harvested when the bloom is fully open but petals are still crisp. Remove lower foliage from cut stems. Deadheading spent blooms extends flowering for weeks. For seeds, allow a few flowers to mature fully on the plant in late season; collect seed heads once they dry, then extract and store seeds in a cool, dry place.

Fun Facts

  • 🌱 Oklahoma Purple is named for the University of Oklahoma, where significant breeding work on disease-resistant zinnias took place. It was developed specifically for superior mildew resistance, making it far superior to many older zinnia varieties.
  • 🌱 Zinnias are native to Mexico and were cultivated by the Aztecs before European contact. The name 'Zinnia' honors Johann Gottfried Zinn, an 18th-century German botanist.
  • 🌱 Oklahoma Purple's deep purple color intensifies in cooler weather; the same plant may produce lighter lavender blooms in peak summer heat and richer, almost magenta flowers as temperatures cool in fall.

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