Romneya coulteri seeds – (Californian Tree Poppy, Matilija Poppy)

Description

Picture thanks to Jelitto Seeds https://www.jelitto.com

This beautiful plant has slightly leathery grey leaves which rise from the woody base in the spring and die down again in the winter. The leaves form a shrub-like structure and from this emerge many fat buds which open out to amazing white crinkle pleated  papery petals to form stunning  white poppy  flowers about 15cm wide , which have deep egg yolk yellow centres.  This  beauty  has won the Royal Horticultural Society award of Merit.

It is an extremely beautiful flower which attracts attention whenever it is seen.

It likes very well drained soil, a little on the dry side. and is not a plant for small gardens reaching about 2 m tall eventually and about 1.5m wide .

Sowing advice

There is varying advice for the seed propagation of this plant.:

The seeds germinate well with the application of GA3 ( Gibberlic acid-3). This can be bought from agricultural suppliers,. we used  the brandname Gibber90.  An extremely small amount of GA3 is recommended ( the amount which will fit on the end of a pointed toothpick )sprinkled over the seeds ,which are placed on a moist paper towel and then enclosed in a plastic bag, and kept at about 20 deg C for approx 4 weeks, following the advice of Dr Deno in his books : Seed Germination theory and Practise 2nd Edition – Introduction June 1 1993. They must be checked frequently for germination and potted up immediately that they germinate. We have tried this method and it works well. Be careful not to overdo the Gibberelin as the seeds may etiolate and not prosper.

Other advice, which we have not tried, suggests the use of smoke treatment as used  in many Australian seeds, see  https://www.owairakaseeds.co.nz/product/billardiera-fusiformis-australian-climbing-bluebell-sollya-heterophylla/ for this method.

Other  advice is to give the seeds a period of moist warmth  -20 deg C  for 4 weeks  ( pot up with a good seed raising mix, moisten ,  and enclose pot in a plastic bag to conserve moisture) followed by a period of cold  4 deg C (ie fridge in warmer areas for 6 weeks).After this take off plastic bag , bring out to about 12- 18 deg C and wait .  They should reportedly germinate in about 2 months .