Makin’ Mangaves

While we leave all the fancy mangave creations to our friend Hans Hansen at Walters Gardens, we continue our work on creating more winter hardy (to 0 degrees F) hybrids. Over the last couple of years, we’ve made several crosses using some of Hans’ hardiest Agave ovatifolia based F1 generation selections, like xMangave ‘Blue Mammoth’ and xMangave ‘Falling Waters’ and crossing them back onto Agave ovatifolia.

The F1 mangave hybrids from Hans’ work, have all lost the monocarpic trait of pure agaves, meaning they will not die after flowering. We are curious what will happen if the hybrids have 2 parts agave and one part manfreda. With most of our crosses, we grow 100-200 of each into 1 qt pots, which allows us to do an initial culling after seeing the juvenile foliage traits.

The photos below are from that process, which happened this week. This is a cross of xMangave ‘Falling Waters’ x Agave ovatifolia ‘Frosty Blue’. The first image shows the diversity in the seedlings. All plants have some degree of glaucous foliage…some more toward blue and others with purple spotting that comes solely from the Manfreda parent. It was interesting that the F2 plants still showed some degree of purple spotting…probably around 5% of the plants.

Mangave seedling variability within a F2 generation cross.
x Mangave ‘Falling Waters’ x Agave ovatifolia ‘Frosty Blue’

From a batch of 100-200 plants, our goal is to select 10% for the next round of in ground trials. We focus on selecting at least one plant for each desirable trait. Those traits include: size (dwarf or large), leaf undulations, spotting density, best blue color, leaf twisting, leaf length, leaf width, overall form, best spination, and variegation.

Below are some of our final selections for the next phase of trials. These will be up-potted into 3 quart pots and overwintered indoors, since we’re already too late for planting outdoors this year. These will go into the ground in spring, after the danger of frost has passed.

Mangave seedlings selected for in ground hardiness trials.
x Mangave ‘Falling Waters’ x Agave ovatifolia ‘Frosty Blue’
x Mangave and Agave hybrids overwintering in a heated greenhouse
x Mangave and Agave hybrids overwintering in a heated greenhouse

Agave ‘Prince of Whales’

Our 2016 century plant hybrid is looking quite lovely in the garden this month. This plant, which we named Agave x victorifolia ‘Prince of Whales’, is a hybrid of the Whale’s tongue century plant, Agave ovatifolia (male parent), and the Queen Victoria century plant, Agave victoriae-reginae (female parent).

Since both parents are non-offsetting, this means that the offspring will grow to maturity, flower, then die. Consequently, in order to be able to propagate and share, we will have to drill out the central core of the plant to trick in to offset. While this ruins the appearance of the original, it’s the only way for this to ever be shared and preserved. This plant has been in the ground since 2018, so we expect to have another eight years (guessing) prior to flowering. Consequently, so we’ll probably gamble on waiting a few more years before performing surgery. Winter hardiness is Zone 7b-10b.

Agave x victorifolia Prince of Whales
Agave x victorifolia ‘Prince of Whales’

Below is a photo of both parents.

Agave ovatifolia
Agave ovatifolia
Agave victoriae-reginae
Agave victoriae-reginae

The Look of Love

If you’re able to visit during this years spring open house, it will be hard to miss the look of love in the air. We have a record 20 century plants in spike in the garden…a number far surpassing any flowering record we’ve set previously.

Agaves are a genus of mostly monocarpic plants…they live their entire lives to flower once, then after experiencing a giant-sized orgasm, they fall over dead. In the wild, many species take up to 100 years to flower, which is why the name century plant stuck as a common name. In our more rainy climate, our century plants typically flower in 12-15 years. Several of our current crop are actually less than a decade old, but their enormous size has already been achieved, so they’re ready to reproduce.

Some species of agaves offset, and in this case, only then central rosette dies, and the offsets continue as is the case with bromeliads. Those agave species which never offset are one-and-dones, but hopefully will leave behind a plethora of seed for the next generation. From the start of the spikes to full flower is usually about 8 weeks. Below are a few of our babies in spike.

Agave ovatifolia ‘Vanzie’
Agave x ovatispina ‘Blue Arrows’
Agave lophantha JLBG-01
Agave x loferox JLBG-014
Agave x pseudoferox JLBG-176

Sex for the Centuries

Since we are limited in the number of hardy century plant species, our only option for more agave diversity in the garden is to create it by crossing existing hardy species together. Here are a few of our recent successes.

Agave x amourifolia is a Plant Delights/JLBG creation from a cross we made in 2016 that combined the genes of three century plants, Agave ovatifolia, Agave lophantha, and Agave x pseudoferox ‘Logan Calhoun’. Our size estimates were that the offspring would mature at 3′ tall x 5′ wide. Here is one of our garden specimens photographed this week, which has already reached 2′ tall x 3′ wide.

Agave x amourifolia

Below is Agave x ovox, a 2017 cross of the two giants, Agave ovatifolia and Agave x pseudoferox ‘Bellville’. We expect this to get huge…perhaps 5′ tall x 10′ wide.

Agave x ovox ‘Large Ox’

Below is Agave x protifolia is a 2016 Mike Papay cross of Agave x protamericana x Agave ovatifolia. We also expect this to get quite massive.

Agave x protifolia

Below is Agave x ovatispina ‘Blue Arrows’, a 2016 Mike Papay cross of Agave ovatifolia x Agave flexispina. We would have expected this to be a mature size, but it’s achieved this in only 5 years, so we think we’re seeing some serious hybrid vigor.

Agave x ovatispina ‘Blue Arrows’

Below is Agave x ocareginae, our 2016 cross of Agave ovatifolia x Agave victoriae-reginae. Most likely, this elegant small grower will never offset.

Agave x ocareginae

Below is Agave x schuphantha, a 2015 Mike Papay cross involving three century plant species, Agave schidigera, Agave lophantha, and Agave lechuguilla. It’s formed a beautiful, symmentrical rosette, which should be getting close to mature size.

Agave x schuphantha ‘Wheel of Fortune’

Sibling rivalry

As a plant breeder, one of the cool things we get to do is observe the diversity that arises from a single cross. In some cases, the diversity shows up in the first generation (F1), while in other cases, the first set of offspring need to have sex with each other for the diversity in the offspring to reveal itself (Mendelian genetics). Fortunately, with agaves, we can see quite a bit of diversity in the F1 populations.

Below is a cross we call Agave x amourifolia, which is our cross of Agave ovatifolia, pseudoferox (salmiana var. ferox of Hort.), and lophantha. Here are three of our selected seedlings from that cross.

Plant #1 below is showing the large size of Agave x pseudoferox and the color of Agave ovatifolia (blue), with little visible influence of the narrow leaf, yellow-centered Agave lophantha.

Agave x amourifolia

Plant #2 below show more color influence from Agave x pseudoferox, but with the compact form influence of Agave ovatifolia.

Agave x amourifolia

Plant #3 below shows equal parts Agave x pseudoferox and ovatifolia, but also, what appears some leaf narrowing we would expect from Agave lophantha.

Agave x amourifolia

Below is Agave x flexiferox, created from a cross of the small Agave flexispina x the giant pseudoferox (salmiana var. ferox (Hort.). Plant #1 shows the small size of Agave flexispina, with the greenish coloration of Agave x pseudoferox.

Agave x flexiferox

Below, Agave x flexiferox ‘Megalodon’ shows the larger size and overall coloration from Agave x pseudoferox, with some added blue tones from Agave flexispina.

Agave x flexiferox ‘Megalodon’

Below is Agave x victoferox, a cross of Agave victoriae-reginae x pseudoferox. Plant #1 below shows the form and size of Agave victoriae-reginae with the color of Agave x psedoferox.

Agave x victorferox

Hybrid #2 below shows the teeth from Agave x psedoferox (victoriae-reginae has no teeth), and a size intermediate between the two parents.

Agave x victorferox 2

Hybrid #3 below shows a larger size and more teeth due to more genes from Agave x pseudoferox. The teeth are much smaller because of the Agave victoriae-reginae genes. The splendid compact form also comes from the Agave x victoriae-reginae parent. This cross almost resembles the Northern Mexican Agave montana.

Agave x victorferox 3

We hope this gives you a small peek into the world of plant breeding and the subsequent evaluation and selection process.

I’ve fallen and I can’t get up

This summer, two of our spiking clumps of Agave ovatifolia became dislodged from the ground during a violent thunderstorm. We wondered if they would still set viable seed despite being without roots, since the energy built up from 15 years of growth was still in the foliage. We made several crosses without having to set up a ladder and it appears that we’ve got good seed set. Nature is amazingly in its desire to survive.

A Phallic Spring

The bees are buzzing with excitement over the impending flowering of five clones of Agave ovatifolia here at JLBG. We’ve never had a year with quite this many whale’s tongue agaves spiking at once, so it should be quite a show. Here’s our Agave ovatifolia ‘Frosty Blue’, which was the first to spike, but the other four aren’t far behind. Full opening probably won’t occur until our summer open house, but in the meantime, they are still something to marvel over.

A whale of a story…mama told me not to tell

We grow many century plants at JLBG and one of our best is the amazing Agave ovatifolia…seen here. This 14-year-old clone will be flowering this May, so be sure to catch the amazing 20 foot+ flower spike at the Spring Open Nursery and Garden Days.

Some our agaves such as this are clones, while others are seed grown. We like the clonal selections for uniformity, but we love the variability we find when we grow plants from seed. A good example is the Agave ovatifolia below that we grew from seed shared by the Ruth Bancroft Garden. Obviously, the mama ovatifolia had an affair, so our job now is to figure out who the daddy might be. The best suspect so far is Agave montana.

Agave ovatifolia seedling, possibly with Agave montana