Pushing nature forward

Our first breeding efforts, in 1984, were with the genus Hosta. We are currently focused on agave, amorphophallus, arisaema, baptisia, crinum, epimedium, hardy amaryllids, mahonia, mangave, polygonatum, rohdea, trillium, and yucca.

Pushing nature forward

Our first breeding efforts, in 1984, were with the genus Hosta. We are currently focused on agave, amorphophallus, arisaema, baptisia, crinum, epimedium, hardy amaryllids, mahonia, mangave, polygonatum, rohdea, trillium, and yucca.

What is plant breeding?

Definition

The purpose of plant breeding is to improve or modify the appearance and vigor of a plant. It is a multistep process that involves combining genetic material from two parents with favorable traits (pollination), followed by cultivating the resulting offspring (seedlings) and targeted selection of plants that exhibit the desired traits (culling). The process may be repeated several times over a period of years in order to strengthen the traits, make them more stable, and increase the vigor of the plant. From pollination to introduction, the process takes 3-10 years, depending on the genus and species.

How we decide what to breed

Our breeding efforts are a bit scattered as are our plant interests, as with anyone with ADHD can attest. We have chosen to focus on genera that have good garden potential, but which haven’t been overbred, or if so, we chose to head in a different direction. Our first breeding efforts, in 1984, were with the genus Hosta. It would be another decade before we branched off into other genera.

We are currently focused on Agave, Amorphophallus, Arisaema, Baptisia, Crinum, Epimedium, Farfugium, Mahonia, Mangave, Polygonatum, Rohdea, Trillium, and Yucca. Below is a bit about each genus we work with. Some genera are crossed by hand, while others work best using isolation blocks, where potential parents are grown side by side, with the proper pollinators nearby. The more breeding work that has already been done with a genus, the less the chances that insect crosses will be able to make significant advances

What makes a breeding program successful


– A good understanding of genetics and heritability.

– A good understanding of how to hybridize plants.

– A good set of breeding goals, and the ability to visualize the desired results.

– A good set of plant genetics from which to work, ideally including a good collection of wild documented species.

– An ability to be able to evaluate selections based on breeding goals, and cull the offspring at an early age. So many breeding programs bog down due to an inability to discard any, or enough seedlings.

– A thorough understanding of all products that are already on the market in the genus with which you are working.

– An adequately sized trial area in which to evaluate plants to maturity. Breeding plants that aren’t trialed well have little long-term value, as gardeners will quickly see through poorly-trialed selections. Good trialing is a numbers game — the more plants on trial, the better the chance of a breakthrough selection.

Our process

We begin any breeding program by first deciding which plant genera we are going to breed. Next, we make sure we have an adequate set of genetics with desirable traits, which includes wild documented accessions, where possible.

We then determine our breeding goals. We do this by first knowing what is already available in the genus, and where improvement or differentiation might have garden value. Then we visualize the resulting offspring. That visualization will often change with each additional generation of breeding, as unanticipated results may open up previously unknown options.

Agave pollen collected
Agave pollen collected

Making the cross

To hybridize plants, we must first understand what it takes to make a cross in each plant genus. Some plants are wind pollinated, while others are insect pollinated. Some plants like cycads and Arisaema need a highly specialized method of pollination. We study each genus to determine when the male pollen is ready and when the female plant is receptive. Dioecious plants, which have both male and female individuals on separate plants, add another layer of complexity, especially with those genera which change sex annually. Breeding ferns is a whole other matter since ferns can’t be crossed until after the spores germinate.

Making crosses is not something that is done on a single day. We usually repeat the same cross every day for 1-4 weeks. Crosses are also generally made reciprocally, which means the cross is tried using each parent as the female pod parent. 

Occasionally, a cross will only work in a single direction (male or female), or the desired trait may only be heritable in a single direction. When one parent is the result of a complex cross, we find that using a straight species as the mother generally results in higher success. It’s also always a good idea to know the chromosome number of both parents, so we won’t waste time trying to make a cross that’s genetically impossible.

Steve Guptill hybridizing an agave
Steve Guptill hybridizing an agave
Agave seedling pots
Agave seed pots

Sowing seed

Just because our cross produces a pod or even seed, doesn’t mean we’ve been successful. There are plenty of plants that will develop a seed pod that contains no viable seed. If we obtain viable seed, they then need to be sown at the proper time. Some seed can be sown immediately after harvest, while other require a dry, cold, warm, etc. treatment for up to 3 months before seed will germinate. Some seed like Mahonias, Agaves, and Baptisias germinate quickly, while cycad seed can take 6-12 months to sprout.

Agave seedlings in cell packs at the nursery
Agave seedlings in cell packs at the nursery

Seedling selection

At some point in the process, seedlings will need to be culled. Culling is simply the act of discarding seedlings. This is done by comparing each seedling to the visualization of the original goal. Without goals and visualization, culling becomes impossible. The lack of the ability to properly cull, usually due to the fear of throwing away an interesting plant, is usually the death knell for most amateur plant breeders. Without being able narrow our evaluation focus, the sheer number of seedlings would quickly become unmanageable.

With some plants we are able to cull when the seedlings are first transplanted into cell packs. We perform a second round of culling when the cell packs are transplanted in 1 quart containers. At this stage we typically discard around 75% of the cell pack plants. A third round of culling is typically done when the seedlings are ready to be planted in the field, at which time we eliminate another 75%. Factors in determining what to discard are vigor, appearance, disease resistance, and their adherence to our breeding goals.

Mangave and agave hybrid seedling selections
Mangave and agave hybrid seedling selections
the final step

Field trials

While many breeders trial plants only in containers, we feel this is a great disservice to the end user since plants rarely perform the same in containers as they do in the ground. This is also why incorrect mature sizes abound in the horticultural industry.

Trialing plants in both containers and in the ground is certainly the gold standard to make sure they are both commercially producible and good for the end user.  The key to a good breeding program is to have a large enough trial area, with good soil/moisture.  Good breeding is a numbers game. The more seedlings that are trialed, the better the chance of producing a new breakthrough plant.

You’ll also need to know how long a trialing period is needed for each crop. For most plants we work with, five years is the minimum in-ground evaluation time.

Agave hybrid in our outdoor trial area

Once you’ve created a new plant, it must be next propagated so it can be introduced or shared. Propagation can be as simple as rooting cuttings, or as difficult as crown cutting or tissue culture. Even within a genus that is propagated by cuttings, not every clone roots at the same percentage. We often find that after a plant passes all the previous steps, it still may never make it to market because of propagation issues.

Agave x loferox JLBG-029
Agave x loferox JLBG-029

Agave hybridization

The genus Agave has long been an interest, ever since Tony accompanied his parents on a driving family vacation to the Southwest US, some 60 years ago. Later, in the 1970s, when Tony was in school at NC State, with Dr. J. C. Raulston, he was astonished that J. C. was able to grow an agave outdoors at the arboretum that would later bear his name. That began an insatiable quest to grow all 29 agave species that are winter hardy in Zone 7b. Once that list was exhausted, the only option for more was to start making hybrids.

The first step was to wait for our garden agave collection to mature to flowering size. While this purportedly takes up to 100 years in the wild, it only takes 10-15 years in a moist climate cultivation. Step 2 was to purchase a really tall ladder. Before long we were ready for step 3, making the crosses. We learned quickly that not all crosses set seed. Only a small portion of our crosses result in viable hybrid seed. Excessive hot weather, timing, and basic genetic incompatibility, all affect seed set.

Seed are ready by early fall when they are harvested and sown immediately. The seedlings are transplanted into cell packs by mid-summer, and are usually ready for the first culling by that fall. At that time, only the best (most vigorous, and most unique) are transplanted into 2 quart containers where they remain until the following spring. If we germinate 500 seedlings of a cross, typically a maximum of 20 would make it to the 2 quart potting stage. The more distant the cross, the less seed usually germinate. It is not unusual to make a cross every day for several weeks in a row, only to find out after the seed harvest that there are 2-10 viable seeds per pod, compared to several hundred in a highly compatible cross.

The following spring, the final seedling selections are planted outdoors in the trial beds, where they remain until we have enough winter cold to test for the winter hardiness. This can often take 5-7 years. Once final selections are made in the ground, the plants are named, photographed, measured, and moved into the main garden. 

At this point, propagation begins. Offsetting agaves are easily multiplied by division and cuttings. For non-offsetting types we developed a coring technique, where we remove the central meristem, removing the Auxin dominance, and thereby promoting offsets. Once mature, the offsets are divided and cored again. This process can be repeated for years until the desired amount of plants is reached. The full process, from making the initial cross to having enough to share, can range from 10-20 years.
 
Our first successful hybrids were made in 2009, when we crossed Agave lophantha with Agave x pseudoferox (A. salmiana var. ferox of Hort.).  Below is a chronology of our successful hybrids. Crosses have been made every year since then, either by our staff or our team of amazing volunteers, Mike Papay and Vince Schneider.

2009   Agave x loferox (lophantha x x pseudoferox (salmiana var. ferox of Hort.) )
2013   Agave x striphantha (striata x lophantha)
2014   Agave x ocareginae (ocahui x victoriae-reginae)
2014   Agave x flexiferox (flexispina x x pseudoferox (salmiana var. ferox or Hort.))
2014   Agave x victoferox (victoriae-reginae x x pseudoferox (salmiana var. ferox of hort))
2015   Agave x flexidigera (flexispina x schidigera)
2015   Agave x schuphantha (schidigera x lechuguilla x lophantha)
2016   Agave x amourifolia (ovatifolia x x loferox)
2016   Agave x ovatispina (ovatifolia x flexispina)
2016   Agave x protifolia (ovatifolia x x protamericana)
2018   Agave x ovox (ovatifolia x x pseudoferox (salmiana var. ferox of hort))
2021    Agave x victorifolia (ovatifolia x victoriae-reginae)
2021    Agave x asperifolia (asperrima x ovatifolia)
2022    Agave x elegantissima (ovatifolia x mitiflora (mitis x polianthiflora))

Arisaema formosanum x consanguineum
Arisaema formosanum x consanguineum

Arisaema hybridization

We were met with significant skepticism and a bit of derisive laughter, when we announced our intention to breed arisaemas. As it turned out, quite a few people had tried crossing arisaema, but few had succeeded.  We knew that the late Georgia plantsman, Don Jacobs had made a successful cross of Arisaema sikokianum and Arisaema takadae (Arisaema x ecotak), so we knew it was possible. 

Our first hybrid, made in the early 1990s was a very wide, intersectional cross between Arisaema fargesii and Arisaema heterophyllum. We subsequently named it Arisaema x fargophyllum ‘Crossing Over’. Thanks to the brilliant work of plantsman Hans Hansen, who was able to multiply it in tissue culture, we were able to share.

Other crosses made and confirmed since then include:

Arisaema x heterburgii ‘Black Snake’ (heterophyllum x thunbergii)
Arisaema x heteroguineum ‘Pirate Flag’ (heterophyllum x consanguineum)
Arisaema x triburgii (triphyllum x thunbergii)
Arisaema x trigens (triphyllum x ringens)
Arisaema x trigesii (triphyllum x fargesii)
Arisaema x tribarae (serratum var. mayebarae x triphyllum)
 
Arisaema breeding is made more difficult by the nature of arisaema genetics. Most arisaema species are diocious (either male or female on separate plants), and they can undergo a sex change each year, so you never know what you will have until the flower opens. Consequently, you generally need lots of luck and/or lots of plants, to ensure you’ll have will have the right sexes at the right time to be successful.

Baptisia 'Blue Towers'
Baptisia ‘Blue Towers’

Baptisia hybridization

Baptisias have been a plant of great interest since the early 1990s. Naturally occurring baptisia hybrids have been documented since the 1930s, but only a few if any of these were ever propagated for gardens. So, in 1998, we embarked on our first botanical expedition focused on acquiring baptisia genetics. I was accompanied by fellow plantsman and plant breeder, Hans Hansen, who also had an interest in the genus. Genetics from our trip were also shared with Dr. Jim Ault of the Chicago Botanic Garden, who conducted the nations’ other baptisia breeding program.
 
Our goal was to re-create many of the naturally occurring bicolor hybrids that had been documented from the wild, while also working on refining the plant form and working to improve the height of the flower spikes. Baptisia are almost impossible to cross by hand, so we let the bees do the work, exercising control over what is planted nearby and from which plants we choose to collect seed. So far, we have been able to make tremendous strides in floriferousness, color, form, and habit.
 
Baptisia seed are gathered in early summer, but we typically keep them refrigerated until December, so the offspring won’t be ready before we have staff time to handle them. Once planted, they germinate quickly and are moved to cell packs. We typically plant between 100 and 200 plants per cross. By late summer, these are ready for the first round of evaluations and usually no more than 18 per cross are up-potted into 1 quart pots. By the following spring, these are re-evaluated, culled further, and the remaining plants and moved into field trials. Evaluations typically take 3-5 years, at which time final selections are made and propagation of named clones begins.
 
Our first few clonal introductions were seed-grown selections of wild species. These included: Baptisia minor ‘Blue Pearls’ (2005), Baptisia alba ‘Wayne’s World’ (2005), Baptisia perfoliata ‘Survivor’ (2005), Baptisia leucophaea ‘Butterball’ (2008), and Baptisia minor ‘Blue Bonnett’ (2015).
 
We didn’t introduce any hybrid clonal selections until 2014, when Baptisia ‘Blue Towers’ and Baptisia ‘Blonde Bombshell’ were released. Since then,  22 additional hybrid clones have been named and introduced. 

Crinum bulbispermum 'Chessmaster'
Crinum bulbispermum ‘Chessmaster’

Crinum hybridization

Since Tony was a young child, he has always been fascinated with crinum lilies. After assembling a huge collection of these long-flowering, durable amaryllids, over 400 taxa, he realized that despite hundreds of years of breeding there is still room for dramatic improvements in foliage, form, flower, flowering season, and winter hardiness, since species like Crinum bulbispermum and Crinum macowanii are winter hardy as far north as Zone 6.

Dr. Dave Lehmiller of Texas will go down as making the most advancements in crinum breeding, although his goal was to study the genetics of the genus instead of having ornamental breeding goals. His amazing work, however, laid the groundwork for us and many other current era breeders.

Crinums aren’t the easiest genus to breed, not because the crosses are hard to make, but because most of the F1 crinum hybrids are sterile. Consequently, it’s difficult to advance beyond the first generation. Backcrosses to species generally work well, but going past this point is challenging. Also, most crinums open in the evening, so crosses are best made just before sunset, which isn’t an ideal time for many plant breeders who don’t live near their breeding fields.

Once final selections are made and named, a significant amount of time is needed to build up enough bulbs for a commercial offering. The whole process, from making a cross to introducing a new crinum, usually takes 10-30 years. Tissue culture is really the only viable option for reducing this time frame to less than a decade. 

Epimedium grandiflorum var. higoense 'Bandit'
Epimedium grandiflorum var. higoense ‘Bandit’

Epimedium hybridization

Our interest in epimediums was piqued thanks to the amazing work of plant breeder Darrell Probst.  We never envisioned breeding epimediums, but when Darrell moved on to coreopsis, we picked up the epimedium torch. Darrell’s introduction of so many new evergreen Chinese species to cultivation opened the door wide for tremendous breeding advancements in the genus.

Most of our work has been focused on hybrids with those evergreen species. The clumps from these crosses are dramatically larger in size with larger flower clusters of larger individual flowers, than the early introductions in the genus, using primarily the deciduous Epimedium grandiflorum as a parent.

Hand crosses are possible with epimediums, but incredibly tedious, followed by the bagging of flowers to catch the seed. We find that significant advances are still possible by simply planting the desired parents together and the growing out the seedlings.

The closer the hybrids are related to the original species, the better the chance of getting viable seed. Epimedium seed germinate in spring and are ready to be moved into 1 quart-sized pots by fall. Some seedlings will flower the following spring, while others will take two years. Once they flower, we are able to make our selections that then move into field trials. Our breeding goals include larger floral displays, new floral colors, branching flower scapes, and extending the bloom season. We now have seedlings that produce sporadic flowers from March until October. Foliage coloration and clump growth are secondary considerations in our final selections.

Once epimedium seedlings go into field trials, they usually remain there for 3-10 years, before anything is selected and named. After selections are made, there is typically a 3 year propagation window to build up enough stock to introduce.

Farfugium japonicum var. luchuense 'Basho Ogi'
Farfugium japonicum var. luchuense ‘Basho Ogi’

Farfugium hybridization

We love farfugium, for their interesting foliage and a spectacular show of fall flowers. With only 2 species in the genus, most of the named cultivars are simply selections of Farfugium japonicum.  Farfugium ‘Last Dance’ is the only named hybrid with both species.

The potential flower traits we’ve worked toward are changing the flower color from yellow to orange, double flowers, and much denser floral shows. Foliage traits include larger leaves, heavy foliar ruffles, split and contorted leaves, and heavy yellow spotting.

Our biggest barrier to farfugium breeding is the late flowering season, which prevents the seed from maturing unless we have a long, mild fall. On years when we get viable seed, they germinate quickly, and we can easily flower seedling in a single year. At this point, they are selected for excessive leaf spotting, floral show, and unique leaf traits, with the best planted out in field trials.

Hosta 'Menorah'
Hosta ‘Menorah’

Hosta hybridization

Our work with hosta began in earnest in 1984. Compared to many plants hostas are quite easy to breed as long as you have compatible parents, good breeding goals, and can exclude bees. Through the years as more and more people began working with hostas, we narrowed our focus first to using lesser known or more difficult to work with species, then to work on fragrance, then finally to work on both branched flower scapes as well as dwarf hostas with exceptional vigor. 

Fragrance in hostas is one of the most difficult traits to breed for, since the only fragrant species opens its flowers at 4-5pm, while all other hostas open between 7-9am. Since breeding for fragrance is such a wide cross, a majority of the F1 hybrids are sterile making the line breeding difficult.

Breeding for reliable branched flower scapes also took several generations to make the trait reliable from year to year and to make the flower stalks sturdy enough to support the extra weight. Our final goal of branched flower scapes and fragrant flowers was achieved with our introduction of Hosta ‘Menorah’.

Our work to create a dwarf hosta with great vigor began with a 1997 trip to the Korean Island of Cheju, where Hosta venusta is native. We brought back a few special selections from the wild, where they grew in expansive pastures. Those were subsequently self-pollinated and the offspring were grown. Each generation, the most dwarf, vigorous plants were selected, until years later we had our breeding parent line created.

We also used the odd mutant, Hosta ‘Blue Mouse Ears’ in much of our dwarf breeding, since it added a unique leaf thickness to the offspring. From there, we made a series of unique selections, which would become our other breeding line. Then both lines were crossed together in array of combinations. This continued for a couple of generations until we achieved our goals of unique plants with small size and vigor.

Mahonia nitens 'Ogisu'
Mahonia nitens ‘Ogisu’

Mahonia hybridization

In the early 1990s, the late J. C. Raulston used to talk with us about his desire to breed mahonias in his retirement. With his untimely death, that unfortunately never happened. So in 2007 we decided to pick up J. C.’s torch and experiment with mahonia hybrids. In 2012, after five years of dabbling with seedlings and trying to understand the genetics, we jumped into the project with more focused efforts.

New species that entered the US around 2000 presented amazing new opportunities for a completely new look and flowering time, compared to the old Mahonia x media types. We began assembling as many species as possible, and so far have used M. eurybracteata, M. nitens, M. gracilipes, M. bodinieri, M. fortunei, M. fargesii, and a couple of un-named species in our breeding. Our goal is to create smaller mahonias that mature around 3’ tall, and have a good floral show.

Mahonia breeding is not a fast endeavor. Seedlings are sown in winter and then transplanted to cell packs in spring. By late summer, these are extensively culled and transplanted into 1 quart pots. If we start with 200 plants of a single cross, we hope to transplant no more than 18 of each.

These quart-size plants then spend the next three months being evaluated under nursery conditions for leaf disease resistance. By the end of this trial, we are able to evaluate the plants for growth rate, size, and uniqueness. By fall, or occasionally the following spring, they are culled again by 50-75% and the remaining selections are planted in the ground. Despite mahonias being shade plants, we perform our in ground trials in full sun in order to subject the plants to as much stress as possible. In the ground, they are trialed for both garden performance and cold tolerance. Our minimum trialing period is five years before final selections are made.

Once final selections are made, the top selections are propagated and sent to horticultural marketing firms to decide which, if any, fit their goals, after which they go into full scale production. Since mahonias are not currently able to be tissue cultured, stock build-up may take an additional 3-5 years or more.

Polygonatum falcatum 'Wedding Bells'
Polygonatum falcatum ‘Wedding Bells’

Polygonatum hybridization

JLBG has maintained an extensive collection of polygonatum for decades, but it was only in 2010 that we realized the potential of a breeding program. By growing many different species nearby in our field production areas, we found that many were crossing on their own. The most exciting thing is that there doesn’t appear to be any barriers to breeding, since we’ve found crosses between very phylogenetically distinct groups.

We currently have a number of interspecific crosses that are being evaluated, including two that have already been named.

Polygonatum martinii x falcatum
Polygonatum commutatum x amabile
Polygonatum falcatum x verticillatum

Rohdea japonica
Rohdea japonica

Rohdea hybridization

We’ve had an interest in rohdeas since the 1970s, long before the genus became popular with American shade gardeners. Since rohdeas are in the same family as hosta, agave, polygonatum, and yucca, they behave quite similarly in how they interbred. While most rohdea breeding is done between cultivars of Rohdea japonica, we now have confirmed crosses between Rohdea japonica and Rohdea chinensis var. watanabei, which we still feel should be its own species.

Like hosta, streaked rohdea produce a large percentage of streaked offspring, although we find these very slow to settle out genetically to a periclinal chimera (an edged or centered form). Stock build-up from a single seedling selection is still quite slow, until tissue culture becomes a better option.

xMangave 'Snow Leopard'
xMangave ‘Snow Leopard’

Mangave (Manfreda x Agave) hybridization

Mangave are our name for hybrids between the North American native genera, manfreda and agave. We realize that new taxonomic studies have recommended combining the two genera into a single genus, but we find them quite distinctive in foliage as well as their monocarpic nature. Consequently, we await further studies before making that change.

We began our mangave breeding program in 2004, after realizing that such a cross was possible. During the next eight years we made several crosses, trying to understand the range of possibilities for such hybrids. We came to the realization that this program could have tremendous commercial potential that was greater than our abilities, so we handed off the entire program of plant genetics to our friend Hans Hansen, who had recently become the Director of New Product Development at Walters Gardens in Michigan. We, and others, continued to ship Hans agave pollen from across the country, while he continued to make crosses and mix up the genes. After years of mangave breeding, it was finally time to reveal the first of Hans’ hybrids to the horticultural world in 2016, with the introduction of x Mangave ‘Pineapple Express’. The following year, five more selections were released including x Mangave ‘Bad Hair Day’, ‘Man of Steel’, ‘Spotty Dotty’, ‘Silver Fox’, and ‘Purple People Eater’.

These early mangave releases proved very popular, but had little winter hardiness, since they were bred primarily as tender perennials to be used for bedding and containers. Due to our zone 7b climate, we were in a perfect spot to tackle the challenge of creating winter hardy mangave cultivars. Currently, the most winter hardy selections (zone 7b and south) are x Mangave ‘Blue Mammoth’ (Agave ovatifolia x Manfreda maculosa), ‘Falling Waters’ (Agave ovatifolia x Manfreda sp.), and ‘Bad Hair Day’ (Agave geminiflora x Manfreda maculosa).

One of the downsides of agave is that most species are monocarpic – the plant dies after flowering. This is not true of manfredas, so the F1 x Mangave hybrids between the two genera also do not die after flowering. Instead, the main rosette dies back to the central core and re-sprouts with a mass of new rosettes within 6-12 months. Some manfredas are deciduous and others are evergreen. Our work now focuses on the F2 generation to see how the backcrosses onto agave perform and if they will remain more evergreen in winter.

Trillium maculatum
Trillium maculatum

Trillium hybridization

With as large a collection of trillium as we have, garden hybrids are inevitable. Not all trilliums are pollinated by the same flies, but those that are, easily interbreed when grown nearby. Trilliums not only cross in cultivation, but we have found a number of natural hybrids in the wild. Over time, genetic barriers break down, populations migrate, and weather events cause out of sequence flowering, all of which can lead to hybridization.

As a general rule, we find hybrid vigor a real thing in the genus trillium. Below is a list of the trillium hybrids that we’ve documented, using non formally published nothospecific names that we originated.

Below are a few of the crosses that we’ve already isolated.

Trillium x curvatum (cuneatum x recurvatum)
Trillium x flexatum (flexipes x sulcatum)
Trillium x foeteatum (cuneatum x foetidissimum)
Trillium x foetulatum (foetidissimum x maculatum)
Trillium x freatum (cuneatum x freemanii)
Trillium x freianum (cuneatum x ludovicianum)
Trillium x ludoissimum (foetidissimum x ludovicianum)
Trillium x ludoviciatum (cuneatum x ludovicianum)
Trillium x luteatum (cuneatum x luteum)
Trillium x macaroni (cuneatum x maculatum)
Trillium x recurvifolium (lancifolium x recurvatum)
Trillium x rugeyii (rugelii x vaseyi)
Trillium x underliquum (underwoodii x reliquum)
Trillium x virile (viridescens x gracile)
 
We have created both seed strains as well as clonal selections of trilliums. Seeds strains are much faster than clonal selections to reproduce. Once we’ve isolated a seed strain and have an adequate seed supply, then it’s a matter of 5 years to produce flowering plants, so we can make 100% sure that all plants are true to the hybrid type. With a clonal selection, it may take 5-20 years depending on whether the plant is a good off-setter or remains solitary.

Yucca 'Silver-Anniversary'
Yucca ‘Silver Anniversary’

Yucca hybridization

Yuccas have long been known to hybridize, both in the wild and for fiber production, but those which have been made for improving the horticultural value seem to be mostly lost. In the wild, Yucca x gloriosa (filamentosa x aloifolia) and Yucca x recurvifolia (flaccida x aloifolia) are the most common hybrids. 

Germany’s Carl Sprenger was undoubtedly the most prolific yucca breeder in history. His 122 named yucca hybrids, introduced between 1897 and 1907, will probably never be surpassed. Sadly, most of his introductions have been lost.

Next in line appears to be J. B. Deleuil, who introduced 15 more yucca hybrids. After him, F.N. Rusanov from Uzbekistan produced another 8 hybrids, between 1945 and 1959. Of the modern yucca breeders, Benny Moller-Jensen leads the way, but many other European breeders are following in his steps.

We think there is still tremendous potential for improving yuccas for better garden value. So far, we have used the following species in our hybrids: Yucca aloifolia, Y. arkansana, Y. campestris, Y. cernua, Y. elata, Y. filamentosa, Y. flaccida, Y. glauca, Y. louisianensis, Y. pallida, and Y. schottii. So far, our only clonal introduction from our breeding was Yucca ‘Silver Anniversary’, which is a cross of Yucca pallida x filamentosa.

It takes many hands, and one Hans

From seed collection, to propagation of the final selection, it takes years and many hours of hard work to introduce new plants to the market. Almost every department of PDN and JLBG contributes in some way to make our plant breeding program work. We would like to thank our team members and volunteers who bring our mission of sharing unique, rare and native perennials to reality.

Vince Schneider, volunteer, Agave and Cacti specialist

Volunteers Vince Schneider, Beth Cleveland, and Mike Papay have made the majority of our agave and mangave crosses since 2016. It’s amazing folks like this who make our wide-ranging breeding efforts possible.

Carl Schoenfeld, Wade Roitsch, Hans Hansen, John Walters
Left to right: Carl Schoenfeld, Wade Roitsch, Hans Hansen, John Walters

In addition to our staff and volunteers, we have an array of adjunct researchers and collaborators around the world, who make what we do possible. This 2023 photo at JLBG show some of our most important collaborators. Carl Schoenfeld and Wade Roitsch are the former owners of the Yucca Do Nursery. I have had the pleasure of traveling with them, and although the US nursery has closed, still have an ongoing plant exchange. They are both close friends, and we are pleased to continue to introduce the amazing plants from their expeditions and breeding work. Carl has now re-established Yucca Do Salta, from his home in Argentina.

John Walters and Hans Hansen of Walters Gardens, have also been very supportive of JLBG, through a mutual exchange of plant genetics. Even after an agave spine poke sent Hans to the hospital, he still maintains a keen, albeit wary interest in both agaves and mangaves. A large number of the Proven Winners introductions, bred by Hans, were possible because of plant genetics shared by JLBG. Conversely, several new JLBG introductions were made possible by their reciprocal sharing. We are very blessed to have such amazing supporters.

We need your support

Help us continue our work by donating to the JLBG Endowment fund. The endowment will generate operational income to preserve, maintain, and build upon Juniper Level Botanic Garden’s plant research, breeding, and garden operations.

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