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Romneya coulteri (California Tree Poppy) seeds

Romneya coulteri (California Tree Poppy) seeds

Regular price £2.55 GBP
Regular price Sale price £2.55 GBP
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Magnificent, tall, sub-shrub with leathery, silver-grey leaves and gorgeous, fragrant, pure white flowers, 12cm or more across, with golden-tasseled centres. Flowers from late summer onwards just when many plants are beginning to fade. Hardy in all but very cold areas and will flourish in pots.

Winner of the RHS Award of Garden Merit

Hardy Shrub (to -5C)
Flowers: Late summer to early autumn
Height: up to 2m
Position: Full sun

Packet of 30 seeds


RHS Award of Garden Merit

This plant/cultivar has been awarded the RHS Award of Garden Merit because it has proved to be reliable in appropriate conditions and a good performing plant. For more information on RHS award of Garden Merit plants visit




These seeds have a double dormancy which needs to be broken before they will germinate, ie. they need to go through a process which simulates the changing seasons.

Pre-sowing Treatment: Wash the seeds briefly with white spirit, then rinse with warm water.

Sowing Instructions: Sow at any time of year, very thinly in pots of an equal mix of sand & seed compost eg. John Innes. Sow on the surface and do not cover seed as light is beneficial to germination and seal inside a polythene bag. Maintain an optimum temperature of 16-20C for 20 weeks, then place the container(s) in the fridge for a further 30 weeks. Then, return to 16-20C and germination should take place. Throughout this process check regularly and ensure the compost does not dry out. Note: Germination can be very erratic, so sow thinly and prick out the seedlings as they become large enough to handle disturbing the rest of the compost as little as possible.

Alternatively, sow as above, and place in a cold frame or sheltered part of the garden and let nature take its course as the seasons change. I would recommend this method for greater success and much less hassle!

Growing Instructions: Transplant seedlings when large enough to handle into 7.5cm pots taking great care not to damage the roots. Grow on at the same temperature for 3-4 months until well-rooted, then move to a coldframe for over-wintering. Plant out the following spring in a sheltered sunny site, 1.2-2m apart.

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RP Seeds delivery - £1.35 and free on orders over £25  

We offer prompt order dispatch within 1-2 working days by Royal Mail.  Delivery time will normally be within 2-3 days but may vary due to the current situation.

Shipping is only £1.99 and FREE on orders over £30

Due to phytosanitary regulations we are unable to send seeds outside the UK.  If a mail forwarding service in the UK is used to send your order abroad, please be aware that we will not take responsibility for orders confiscated by customs.


If an order is returned to us as undelivered by the postal service, we will refund the cost of the products purchased, not the delivery charge. When a service other than standard delivery is used, we will also deduct this from the refund (eg. signed for, special delivery or courier charges).  It is the customer's responsibility to ensure the delivery address on the order is correct. 

Please report any orders delivered damaged or incorrect, and any missing orders not delivered within 14 days of the order date by emailing us:




All our seed packaging and most of our postal packaging is paper based and can be recycled.

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Store seeds in a cool, dry place.