Hostas have always been popular, and blue leaved Hostas are very sought after for their colour.
The blue foliage of a Hosta is not caused by blue pigment, as you might think. The blue appearance is caused by a thick accumulation of wax on the outside of an otherwise dark green leaf. A lot of blue leaved Hostas are less blue than others. The thickness of the wax coating determines the intensity of the blue colour.
The intensity of the blue colour does lessen in certain conditions. A wet, humid and sometimes hot climate, the wax coating on the leaf degrades, leaving the natural ‘green’ colouring below. This is why blue Hostas often turn green over the season.
Keep these blue Hostas in plenty of shade. The direct sunlight can decrease the waxy coating and turn the leaf greener.
Try not to irrigate from above as too much water can also reduce the waxy layer, making the Hosta less blue & more green.
You may also find that more established, well rooted specimens have a more intense blue colour than the younger ones.
Do not worry, they will be back to normal the next season, when they re-emerge in the spring.
A little bit of history - Blue Hosta origins.
Virtually all Hostas originate from just two parents Hosta sieboldiana and Hosta Tokudama.
Hosta sieboldiana has very thick, round, corrugated powder blue leaves topped with white flowers. These flowers appear in early spring and rise just above the foliage.
Hosta tokudama, has more rounded, cupped blue leaves, than Hosta sieboldiana, and a much slower growth habit.
The most important breeding for blue Hostas in the early days of Hosta breeding was done by the late Eric Smith while working at the famed Hadspen House in England. One year, a late-flowering small, glossy green Hosta, Hosta 'Tardiflora' (a selection of Hosta longipes) was in bloom, and thanks to a rare occurrence, the spring flowering Hosta sieboldiana produced a rare fall stalk of flowers. Being a plantsman, Smith seized on the opportunity and began to make a series of crosses between the two plants.
Smith carried on breeding from his newly created Hostas, and eventually created a number of offsprings with characters of both parents, with both white and lavender flowers.
Some of his named blue varieties were Hosta Hapsden Blue, Hosta Halcyon, Hosta Blue Wedgwood, and Hosta Brother Ronald, plus many others.
The next big breakthrough was the fragrant blue Hosta, from Hosta plantaginea, he created Hosta Fragrant Blue.
Next was the creation of Hosta Elvis Lives, in 1995, from Hosta Halcyon, but with longer elegant ruffled blue leaves.
Work on the blue Hosta was carried on, years later, by Hans Hansen who create Hostas with long, narrower blue leaves with a more intense ruffling, which lead to the introduction of Hosta Neptune. Hosta Neptune was subsequently used to create Hosta Waterslide (2018)
By combining Hosta Neptune genes with Hosta Niagara Falls, Hansen was able to create Hosta Diamond Lake (2018), which was the first large round blue leaf Hosta with wavy margins and good heat tolerance.
Plant Delights, in the USA took a different direction with blue Hostas trying to create more dwarf blue Hostas.
Enough of the history of how the blue leaved Hosta came about. What you want to know is which are the bluest varieties.
Partly it will depend on how the Hosta is grown, given the earlier reasons for losing any blue colour. Given great conditions, it will be hard to beat Hosta Love Pat, and Hosta Blue Angel.
One of our favourite blue Hostas is Hosta Blue Mouse Ears. A miniature blue Hosta with magnificent character. Strong as an ox, beautifully formed and produces a wonderful almost blue/purple flowers in June, sitting just above the crown of true-blue colouring.
Hosta Love Pat. A good heavily corrugated, deeply cupped, with blue good strong coloured leaves. A medium to large Hosta with white flowers. Slug resistant as well.
You also have Big Mama Big Daddy, Blue Cadet, Blue Umbrellas, Krossa Regal, Lakeside Beach Bum, Elegans, Abiqua Drinking Gourd.
The list goes on. Everybody has their own blue favourite, and they are all different.
No doubt the breeders will carry on and produce many more varieties for our delectation.
To learn more about Hostas, you may be interested in reading : What Are the Common Mistakes to Avoid When Growing Hostas?, Ways to Protect Your Hostas from Slugs and Snails and "Uncovering the Advantages of Bare Root Hostas:
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John Plant
Rewela Hostas
Hi,John thanks for another lesson on hostas your knowledge is much appreciated and I look forward to receiving your emails.