Sunday, May 26, 2013

Make Your Own Itohs

By Reiner Jakubowski

240-07 (Rare China x Golden Era)
240-02 (Rare China x Golden Era)
The Itoh Group hybrids are peonies, which result from the cross Lactiflora x Lutea Hybrid.
Lactiflora here means the Lactiflora Group, which includes all the cultivars believed to have descended over hundreds of years of breeding from the wild species lactiflora.  It is the convention in controlled breeding that the female parent is listed first, therefore, Lactiflora (the seed parent) pollinated by Lutea Hybrid (the pollen parent).  The Lutea Hybrid Group peonies traditionally result from crosses between the Chinese and Japanese tree peonies (Suffruticosa Group) and the yellow-flowered Paeonia lutea, and later the dark red flowered P. delavayi. Today the taxonomists have decided that lutea is only a colour phase of delavayi.  Lutea hybrids were originally bred
for yellow flowers; but, today are available in a wider colour range.  The Lutea Hybrid Group brings into the cross distinctive characteristics, such as yellow or variegated flowers, rapid growth, good vigour and late flowering.
There is no magic involved, only perseverance, patience, and a little luck. Anyone can do it. The most important thing is to have a fertile pollen parent and initially one of the proven Lutea Hybrids will give more certain results. There are several choices; 'Golden Era', 'Golden Experience', 'Alice in Wonderland', and 'Alice Harding' are good choices if you want yellows. Try 'Boreas', and 'Chinese Dragon' if you want red Itohs. The colour of the Lactiflora parent also plays a role in colour and you may not get what you expect, so these are offered only as suggestions.
My experience has been that the Lactiflora side of the cross is not so critical and you probably already have something suitable growing in the garden. My preference is to use double or  semi-double flowers because these have given a higher proportion of hybrid blooms showing doubling tendencies than have the singles or bomb forms that I have used. I have seedlings from 'Fragrans' (bomb), 'Rare China' (semi-double), 'Adolphe Rousseau' (flower-in-flower doubling but usually so open a flower that it shows as a semi-double). I also have seedlings from other Lactifloras ('Glenny Carlene', 'Susan B. White', 'Doreen', 'Marie Crousse' and others), but these have not yet bloomed.
240-10 (Rare China x Golden Era)
253-01 (Adolphe Rousseau x Golden Era)
274-39 (Fragrans x Golden Era)
It is best to make protected crosses – that is, to take precautions to prevent contamination from unwanted pollen. This does mean having to strip the intended seed parent of petals and stamens before the flower opens, and then apply the wanted pollen on the stigmas, followed by covering the fertilized flower with either a paper bag or envelope. It is also essential that you tag the pollinated flower so that you know at harvest what the parentage was.  I use a number for each cross; thus #1022 is 'Susan B. White' x 'Golden Era'; #1116 is 'Glenny Carlene' x 'Alice Harding'; and #1229 is 'Fragrans' x 'Alice in Wonderland'. When the seeds germinate and I have seedlings growing, they retain the cross number until I decide whether I will keep them or will cull them. If I keep them for further observation, I just append a number to the cross number – for example, 274-45, 274-39, and 274-43 are all from the cross 'Fragrans' x 'Golden Era' made in 2003. Seedlings 240-02, 240-07, and 240-10 are from 'Rare China' x'Golden Era' also made in 2003; and, finally 253-01 is from 'Adolphe Rousseau' x 'Golden Era'.  The Itoh Cross (Lactiflora x Lutea"Hybrid) has become relatively easy to make, provided you use a known fertile pollen parent. Some years I have more seeds than other years for reasons I do not fully understand; but I usually get a few seeds every year. If you make enough of these crosses you should get some seeds.
descended over hundreds of years of breeding from the wild species lactiflora.
274-43 (Frangrans x Golden Era)
 If you want a bigger challenge, then make the cross in the reverse direction, using the Lutea Hybrid as the seed parent and the Lactiflora as the pollen parent. 'Reverse Magic' (Don R. Smith, 2002) is from 'Age of Gold' x lactiflora 'Martha W.' Also possible, but very difficult, is to use one of the Suffruticosa Group tree peonies instead of the Lutea Hybrid.  'Impossible Dream' (Don R. Smith,
2004) is from 'Stolen Heaven' x 'Martha W.' Note that this cross was made with the tree peony as the
seed parent.  If you make your own Itohs, always look for pollen from your seedlings. Pollen allows you to try back crossing to one of the parents, or to cross Itoh x Itoh. I have  
274-45 (Fragrans x Golden Era)
found two of my seedlings with fertile pollen and have seedlings from Tolomeo #22, Tolomeo #58, 'Fragrans', and 'Doreen', all pollinated with 274-39. (The numbered Tolomeo seedlings were raised by Irene Tolomeo in California and are the lactiflora parents of 'Sonoma YeDo' and 'Sonoma Halo'
respectively.)
Information on growing from seeds is available from the Canadian Peony Society, or contact Reiner Jakubowski at the Society’s mailing address or by email at reiner@kw.igs.net should you have any question.

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