30/05/2018 - Bluji Fade and early senescence

Today we had the very first Ipomoea nil flowers of the season on an unexpectedly early Bluji Fade variety. The variety looks quite nice. A thick white margin around the edge with a dark blue band on the inner edge. This band fades into a lighter blue until it reaches the pink throat. I'm not seeing any white spokes which are typical for Youjiro cultivars but they might still pop up on future flowers. We'll have to wait and see.

Bluji Fade

As is quite usual the first flowers on this young plant did not open fully and had some trouble with premature senescence. Flower senescence is the terminal phase of developmental processes that lead to the death of a flower, which includes flower wilting, shedding of flower parts and fading of blossoms. Ethylene is the major regulator of senescence in Ipomoea nil.

Brown stamens indicate premature senescence.

Premature senescence often leads to the stamens (male sexual organs) dying before they get a chance to release their pollen and pollinate the flower (you can see they are brown in the second photo). This means it's unlikely these flowers will produce seeds. The second flower not opening also means pollinators could not reach it.

The subtle pink hues in the blue parts are an indicator of senescence.

One of the interesting parts of senescence is that it can cause some spectacular colour changes, especially in blue varieties. Blues tend to fade to pink or purple while pink flowers don't usually show much of a colour change.

High temperatures and intense light can cause a flower to wilt before you can see the colour change however. Overcast and cooler days are less harsh on the flowers so they stay intact for longer. Below is a very nice example of the same flower several hours apart. The plant was taken indoors the night before the flower opened so the plant spent its day in a much cooler, low light environment.

Seiryu around noon.

Seiryu in the evening.

The first picture was taken just before noon while the second picture was taken around 6pm (morning glory flowers seldom last this long when grown outside). You can really see the blues changing to pinks and purples making the flower look even more spectacular.

The greenhouse is looking great. We've been having a bit of rain lately but the temperatures are still unusually high so the garden is loving it. There's still a lot of seedlings to plant and I'm running out of space. I will have to start moving some plants outside soon. And once the other ones get bigger they will need to be spaced much further apart.

I'm also enjoying my first dwarf varieties this year. These varieties do not vine and stay very low, making them ideal for growing in pots without trellis. This makes them much lower maintenance. The Sun Smile series has beautiful crystal variegated leaves which is enough reason to grow them already. This one is a light blue Sun Smile. My first two attempts at germinating Sun Smile Violet failed however but I finally managed to get seedling going. I've also got a couple of mixed Sun Smile seedlings going.

Sun Smile Blue

On the first of June we should be seeing the first two Ipomoea purpurea flowers. Two of the flowers on one of my Shiva varieties are almost fully developed now. Lots of the purpureas are loading up with buds. The other Shiva plant has ridiculously large leaves and thick vines compared to all the others. It looks like it's on steroids.

I will finish planting up this row tomorrow. You can see the large leaves of the Shiva variety on the extreme right.