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Delphinium 'Pacific Giant Astolat'

Delphinium Elatum


Pacific Giant Astolat delphinium flowers are colored rosy-lilac. The bees are raspberry/black.

Huge 3 in. double summer flowers are excellent for cutting. When first flower spike is removed immediately after bloom, additional spikes quickly form. Plants grow 4-7 ft. tall, need staking to protect heavy flower spikes from the wind. The palmate-shaped leaves are large.

Pacific Giant Astolat delphinium is a dramatic plant for the cottage garden or the back of borders. Winter hardy to zone 3.



Plant life cycle: Perennial

Site: Sun/part shade

Heigt: 4-6' Feet tall

Days to maturity: 105-125 days

Sow: Surface, press into the soil

Plant spacing: 12-18"

Approx seed per packet : 50


  • FastraX Perennial- does not need vernalization
  • Bred for excellent flower form and stem quality
  • Holds well at retail and in the vase



Culture guide


Background plant, cut flower


Sow time

Outdoor forcing: March-April; Indoor forcing: December-May

Sowing method

2-3 seeds per plug



20-30 days at temperatures of 59-68 °F (15-18 °C).

Growing on

Grow on at 60-65 °F (15-18 °C)



Use a well-drained, growing substrate with 10-30 % clay, 0-15 % parts (e.g. bark, sand, perlite), 1-2 kg /m³, complete balanced fertilizer. 2-4 kg/m³ slow release fertilizer (3-9 months), iron-chelate, micronutrients, pH 5.5-6.5. Field: well-drained, moderate nutrition supply, humus, loamy soils. Standard fertilization:60-80 g/m² slow release fertilizer (potassium balanced). Do not improve the soil with peat. Keep the soil open.



Grow at 15-18 °C (59-64,5 °F) or outdoors. In winter indoors frost free at 3-5 °C (37,5-41 °F) or outdoors. Outdoor fleece cover and dry substrate needed. In spring the plants start to grow for 10-12 weeks at 15-18 °C (59-64,5 °F). A chilling period for flower initiation is not required.



High fertilization levels are required. Fertilize the crop weekly with 100-150 ppm nitrogen (at 2 kg/m³ slow release fertilizer in substrate), using a complete balanced fertilizer. Avoid high ammonium and high nitrogen levels. Don't fertilize after flowering or after early September. In spring fertilize with 100-150 ppm nitrogen using a complete balanced fertilizer. Prevent magnesium deficiency by applying magnesium sulphate (0,05 %) 1-2 times and in case of Iron deficiency apply iron-chelate for 1-2 times. The fertilization with slow release fertilizer is preferred to fertilization with complete balanced fertilizer, because the roots are very sensitive to high salt levels in substrates. Avoid high fertilizer concentrations, it is advisable to fertilize several times with low concentrations weekly. Field: After harvest fertilize the plant additionally with 60-80 g/m² of a slow release and potassium balanced fertilizer. Don't fertilize after flowering.


Harvest: Cut stems 6 in. (15 cm) above ground to prevent Root Rot. Harvest when 25 to 30% of flowers are open. For annual cycle: from early transplant (January/February); first harvest after 12 to 15 weeks; then next 1 or 2 harvests 5 to 6 weeks later. Second and third harvests give best quality stems.


Vase life : up to 7 days

Delphinium 'Pacific Giant Astolat'

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