We have in our garden two species of Portlandia that have been flowering for the last 3 years. As they flower regularly and pollen was available I decided to remaking a cross between them to see how the genetic traits of each parent might be expressed.
Like the pea experiments by Mendel, the two parents of Portlandia have very different plant characteristics. Portlandia proctorii is a medium sized shrub with 3 inch long red flowers. Portlandia grandiflora is a larger shrub with 6 inch white flowers. The differences can be seen in the photographs bellow.
The original cross of Portland’s proctorii x P. grandiflora was made at Fairchild Tropical Gardens. The original cross produced plants with red flowers on a plant similar in character to P. proctorii.
I crossed the two species, using P. proctorii as the seed parent. In other genera and in many species the growth of the pollen tube down the style of a flower is specific to that’s species style length. Therefore I used the pollen from the longer styled species as the pollen parent.
The pollen from the flowers of P. grandiflora were collected and stored in the refrigerator until each flower of the seed parent was ready to be pollinated. In making the actual crosses the floral tubes of the unopened flowers were cut away to expose the stamens and style of each flower to be crossed. This was done due to the fact that the stamens matured before and during the time each flower opened. If emasculation of the stamens was not done it would have allowed for self pollination to occur.
The stigmas are very small to the naked eye and even with a lens, it was difficult to determine when the stigmas were receptive. I decided to hand pollinated each flower over a 3 day period, to assure that the sigmas were mature and to give the pollen the best chances to germinate and increase the chances of fertilization.
Seven flowers of the parent plant were pollinated in the spring of 2019 and the first 2 pods matured on 10/19/2019. The seeds were planted on 1/1/2019 After the seed pods dried and dehisced. I will post germination data as it becomes available.
The following images are of the seed pod and seed collected.
As of this date, I have images and more information regarding my work with Portlandia. The seeds have germinated but viable seeds are few in this first production of seed. Further crossings will be made to develop a large enough population(100 mature plants) to show any results.
There may be inhibiting factors with regards to seed germination as the number of seeds that actually germinated is very low. Time will tell and I will update if germination continues.
The following image shows the seedlings that germinated from the seeds collected.
Dibble, Dribble & Blooms 
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