Hosta FAQs: Where do hostas come from?
Dew you know
what to dew?
While there are lots of places online to find information about hostas (see our links), and of course a number of books you can buy for ready references, we didn't feel that there was a good place online for FAQs (Frequently Asked Questions), as experience with the American Hosta Society's Facebook page has shown. We hope you find this useful. The good stuff is at Part I. Hosta problems are at Part II. And finally a little one-question essay on growing hostas from seeds (scroll down for FAQs below).
Can I grow hostas from seeds?
Yes, but... First recognize that very few hostas will come true from seed (look like the parent plant). It is especially important to recognize that seeds produced by variegated hostas will almost never grow into variegated plants. You can, however, produce a large number of attractive plants in a short time. Over half of hosta cultivars came from seed grown by home gardeners and by hybridizers. (The rest are sports, or mutations, of other hostas.) Not all hostas will make seeds (see below), and even those that do might not make a pod from each bloom. Hosta blooms that get pollinated will start to form pods. If the pods fall off before they are ripe, then the seeds inside were probably not good.
It will take about 6-8 weeks from bloom (pollination) for each pod to ripen. The pods will start to yellow after that, and eventually dry and split open. You’ll want to pick the pods before that happens, or tie a mesh (organza) bag over the pod to catch the seeds. If you picked the pods, you can carefully split them open to reveal the six chambers holding the seeds. Each seed is a small kernel at the end of a papery black wing. If the wings are white, the seeds are not good. I put the seeds from each pod into a paper coin envelope labeled with the parent hosta(s), date, etc. If you let them dry a few days, you can rub off the papery wing, as it is easier to plant only the kernels. I do this in the palm of one hand over a piece of waxed paper, as many as 20 at once. This lets you count the seeds more easily, as each wing may not have a seed kernel. One pod might make 30 or more seeds, although some might have only a few. See pictures of seed-cleaning here.
To grow the seeds, you don’t have to wait if you don’t want to, although there is some evidence showing that a month in the fridge increases germination rates. I start mine in mid to late winter. Grow the seed in a sterile seed-starting mix, just covering the seeds. One innovative method hybridizers are now using is to make holes in the bottom of plastic drink cups (see below), which makes it easy to label each with the parent hosta(s); each cup can hold 15 seeds or so, and the cups fit easily into a tray for watering. Keep the soil barely moist. Most people cover them with a humidity dome, or, in the case of drink cups, a second smaller clear cup. If you’ve ever grown tomatoes from seed, it’s not very different. A warm (75 °F) place is best, or use a seed-starting heat mat. Germination takes from about 10–20 days. Hostas are monocots, meaning a single leaf appears first. Gently tuck in any sprouts that push themselves out of the mix. Continue to keep the soil moist but not wet. It is best to water the tray so they take up water from the bottom. After the seedlings have 4-6 leaves, you can feed with a weak water-soluble fertilizer, and take off the humidity domes.
Hosta seeds don't need light to germinate, but they will need good light once they do. This can be a simple as fluorescent (or LED) "shop lights," or could be more elaborate if you get really serious about it. For shop lights, they should be just a few inches above the leaves, which at first means almost touching your humidity domes. Some people run the lights 24/7, but you should at least wean them from constant light before it's time to move them outside. I switch from constant light to 18 hours of light once they're growing well.
Once the sprouts start to grow, you face the hard task of deciding which ones to keep. Hybridizers may start “culling” their sprouts after only a few leaves are showing. Carefully tug out the ones you don't want to keep (you'll be surprised at how long their roots are) and tuck in the ones left behind. Using the drink cup method, though, I find that I can grow 6-8 seedlings to good size in a cup before they need to be separated. You may want to put them into new cups or into nursery pots, to give them a little more TLC before they go into the ground. Hostas started from seed in February should be happy to go outside into a shady location in May, and into the ground by September. They might even bloom their first year!
That’s the basis of growing any hosta seed. The question is: which seeds are worth growing? For practice, any seed will do. Start with easy seeds from H. ‘Elegans’ or something similar. Then think about what interesting traits you’re looking for, and grow hostas with those traits. Then think about making crosses by transferring pollen from one hosta to another. You’re a hybridizer! Still, be aware that there are over 10,000 different named hostas out there, and you’ll have to work pretty hard to create something new and different. Serious hybridizers may grow 10,000 new hostas each year, and have hybridizing programs that are several generations deep, before they decide on introducing a new plant.
Seed-starting images: Seedlings at 4-leaf stage (after first culls), Seedlings under humidity domes (different year/cups),
Seedlings at "up-cupping" stage to single plant per cup (discarded seedlings at left), and
Seedlings (first- and second-year hybrids) planted in a raised bed. D. Teager photographs
More FAQs about seeds
What hostas DO come true from seed?
Self-pollinated flowers of plants that are true hosta species (H. venusta, H. kikutii, et al.), or single-color selected cultivars of species (sieboldiana ‘Elegans’, venusta ‘Tiny Tears’) will produce seedlings that will be very close in color and size to the parent plant. Check the heritage of your hosta to see if this applies.
What will seedlings from other hostas look like?
Most will be plain green, although a variety of leaf shapes and sizes is possible. Most hostas carry the latent trait for gold leaves, so some seedlings may be yellow or gold, especially if a parent is gold. If the hosta has "blue" leaves in its heritage, then many of its seedlings may produce the waxy coating that makes "blue" leaves.
How do I get variegated seedlings?
There is always a small possibility that a seedling may mutate to a variegated form. But for true variegated seedlings, it is essential that the pod parent (female plant) be a streaked variegated plant. (See Lingo page if you are unsure what this means.) Usually the variegation on these plants is unstable, and this instability is passed to the offspring. Streaked offspring will usually then stabilize as a single colored or variegated form, although this may take several years (with different eyes producing different results).
What about fragrance?
Fortunately, fragrance is a trait that can be passed on from either parent. Unfortunately, because H. plantaginea (the ancestor of all fragrant hostas) blooms in the evening, its pollen and ovaries are ripe for use at the wrong time of day to make cross-pollination an easy task. Some of the newer fragrant cultivars, which bloom at more typical times, could be easier to use for breeding new fragrant hostas.
Do all hostas make seeds?
No, some hostas are effectively sterile, setting seeds extremely rarely. Of these, ‘Undulata’ types and ‘Lancifolia’ are well-known. White-centered hostas will generally not produce viable seeds even as they make "white" pods. Many ‘Fortunei’ types (including ‘Francee’, ‘Minuteman’, ‘Hyacinthina’, and ‘Gold Standard’) are weakly fertile, rarely producing viable seed. On the other hand, most Sieboldiana (think ‘Elegans’) and Tokudama types are extremely fertile, producing abundant seed. The species H. ventricosa has a special fertility: it is an apomictic tetraploid that can set seed without being pollinated. In between are most cultivars: many set seed easily, but some are essentially sterile or set seed only with great difficulty. Seed set is strongly dependent on weather; wet days, cold days (below 65 °F) and hot days (above 85 °F) will often result in failed seed set. Serious hybridizers will move their breeding stock into screened rooms or even indoors to prevent undesired pollination and improve the weather conditions for breeding.
How do I know if my seeds are self-pollinated or cross-pollinated?
Hosta flowers are only open for one day, so they are engineered to be self-pollinated (the pollen is ripe at the same time the pistil is ripe to accept it). So unless you protect the flower from self-pollination, many of the seedlings will be self-pollinated or pollinated from other flowers on the same plant. Natural hybridization by busy bees is possible, of course, depending on what and how many other hostas are blooming at the same time. To ensure cross-pollination, however, it is necessary to transfer the pollen yourself while at the same time preventing insects from pollinating the flower first! This generally involves flower surgery, removing the unneeded stamens and taking away the petals that bees would use for landing pads in spreading and gathering pollen and nectar.
For much, much more information, there are a few sites on the Internet giving guidance on growing seeds, and a few forums on Facebook and elsewhere for hybridizers. I find the tutorial by Josh Spece at In the Country Garden and Gifts to be the best source, with more technical information than above but not too hard to get through in terms of discussing plant genetics. Good luck!