Hosta FAQs: All the help in one place!
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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, as a complement to the other "About Hostas" pages on this site.
Just click on the little ˅ at the end of each question to open (and then collapse) the answer.
What is a hosta?
Hostas are a group of plants (genus) native to Japan and eastern Asia. There are about 40 species of hostas, but they interbreed fairly easily to produce thousands of cultivars. (See Lingo page.) While they are often called “hosta lilies,” they are in fact more closely related to agaves (those spiny succulents) than they are to daylilies or true lilies. They are perennial, meaning they will go dormant for winter but should come back year after year. They do require dormant phase — a period of cold temperature — in order to survive year after year, so don’t be tempted to use one as a house plant. They will grow in climate zones 3 – 8 (in North America, that means well into Canada almost to the Gulf coast), provided they get enough water.
What is a hosta society?
Officially, most are 501(c)3 organizations for educating the gardening public about hostas. Informally, they are great groups of people who get together to learn about hostas, to buy and sell hostas (through auctions or open sales), and to see beautiful private gardens that usually feature hostas. There are many local societies in North America, all under the loose umbrella of the American Hosta Society. The AHS publishes a high-quality journal, supports scientific research projects on hosta pests and diseases, manages the registration of new hostas, and supports the national convention of the society. Membership is not expensive, so join up and meet hosta lovers IRL (in real life)!
What should I use to fertilize my hostas?
Hostas are actually pretty efficient at getting what they need from the soil, so if your soil is good, you may need no fertilizer at all. Many people (especially commercial growers) will use fertilizer, though. Any all-purpose fertilizer will do. Milorganite is used by many as it has additional deer-repellent properties. Hostas in pots should be fertilized a few times a season (or with a slow-release formula).
Should I mulch my hosta beds?
For most gardeners in the US, the answer is “yes.” Mulch helps hold in moisture and keeps down weeds. You can use any shredded wood/roots/bark product, or mulch with shredded leaves or even grass clippings. In general stone products do not make good ground cover for hostas, although in smaller pots or trough gardens it may be nice. Be sure not to pile mulch up around the crowns of hostas as it can cause rot problems. A nifty way to solve this is to place upside-down nursery pots over the emerging crowns in spring, toss mulch over everything to the depth you want (1-3 inches is good), and then remove the pots to leave an unmulched hole around the crown. The hosta mound will expand to hide the hole. Do beware that voles can use mulch as a nice way to tunnel through your beds to get to your hostas.
Should I water my hosta beds?
Yes, you probably should. In their native habitat, hostas receive as much as 50" of rain during the growing season. While most will handle the higher heat levels they see in North America compared to Japan and Korea, they cannot adapt to low water levels. Commercial growers will see that their hostas get 1/2" of rain three times a week. Hostas in pots will especially need regular watering, but let the soil dry somewhat between waterings so you don't cause rot. On the other hand, hostas can be quite dry in the winter when they are dormant; avoid piling snow on them during winter.
When is the best time to move/divide my hostas?
If you’re leaving the hostas intact, you can move them at any time you need. Ideally you get them settled in (don’t forget to water regularly) before the first hard frost. Dividing the clumps causes more stress to the hosta, of course, so it’s best to do that in spring (when they have plenty of time to recover and look nice) or in late summer (when they won’t be looking so nice for the rest of the season anyway). Bob Solberg, of Green Hill Farm in North Carolina, divides most hostas for the purpose of increasing stock in late summer, but believes that siebodiana-type hostas (like ‘Elegans’) don’t like this, and prefer division early in the season.
My hosta has a part that looks different from the rest of the plant. What do I do?
Your hosta has probably produced a mutation, known as a “sport.” (See Lingo page.) If your hosta is variegated but the sport is a solid color, then you probably don’t want it. As a first pass at stopping the conversion to the solid color, see if you can simply snap off the eye (shoot or division) at the base of the plant. If it comes up the next year with more of the solid color, you should dig up the plant and perform a bit of surgery to isolate the part you want to remove (for keeping or discarding). You’ll also want to do this if you want to save the part that’s a different color (say it was a solid hosta but now has variegation). Untangle the roots (by soaking in or washing with water), then use a sharp knife to cut the crown (central structure) around the eye or eyes you want to separate. Some hostas may simply break apart to release the divisions. Then you can replant your original hosta. If you want to compare your sport to what others might have found, use Hugo’s database to search for the original plant, and then look at the list of offspring (sports and seedlings) that he helpfully provides.Note that some hostas, particularly the white-centered Undulata forms, may have color changes through the season, or later flushes of leaves may have a different appearance from spring leaves. Be sure you can tell the difference between normal color changes and true sports.
Should I cut down my hostas in the fall?
Most people will opt to wait until the leaves die back, so you can rake them up when they easily separate from the crown. Yes, if you leave the rotting leaves in place it does return nutrients to the soil, but it can also help spread some diseases. It also can look unpleasant. Better to collect the leaves and compost them so that any pests get cooked out, and then use that nice compost the next year.
I don't like hosta flowers. Can I cut them off?
First is to know that your hostas are free of disease (See FAQ Part IIa) before going from hosta to hosta and cutting off flowers. If tools are not well-cleaned between plants, you can transfer the disease.
Second is that many hosta flowers are pretty. If your hostas are mostly Undulata types, then they're admittedly not very attractive. Buy hostas with prettier flowers (or even fragrant ones). Many people see hummingbirds visiting them; I only see happy bees, so consider that as well.
Third is that blooming is part of the hormonal, seasonal life cycle of the plant. If you cut off blooms before any open, the hosta can get confused and try to make more blooms, taking energy away. Let a few flowers open on each hosta before cutting, if cutting you must.
Fourth, go ahead and cut the blooms after blooming is finished, unless you want the seeds from that hosta. If you don't have a good hybridizing program, your seeds are unlikely to be really good hostas (compared to those produced by careful hybridizers). But don't let me stop you from having fun by trying to grow some. See FAQ Part III for a brief tutorial.If you do want to collect the seeds, it takes about two months from pollination to the point when seeds are ripe. The pod may still be fairly green at that time, but the seeds inside should be fully black: a small kernel at one end with a long, flat “wing.” Once the pods fully ripen on their own they can split open and spill the seeds—perhaps giving birth to new hostas we call “weedlings”—so if you want to collect them you’ll have to catch them first.
Can I grow hostas in containers?
Sure! Here’s an entire web essay on the topic.
Can I grow hostas as houseplants?
You probably shouldn't. They require a dormant cold period (in case you missed that above), and will die of exhaustion if they don't get to sleep. They would, however, be fine indoors for a few weeks during the growing period if you want to use them for decoration. Some hybridizers bring their prized plants indoors during the blooming period so they can protect the flowers from undesired cross-pollination.
Should I label my hostas?
Keeping track of your hostas becomes important one you're bitten by the bug. Visitors to your garden will want to know which is which. One way to keep track is to photograph each bed and use photo software to label each plant. Others use hand- or computer-drawn maps.
Can I grow hostas in full sun?
This is truly a Frequently Asked Question (or its variation, "What hostas grow in full sun?"). A better question is: Will any hostas thrive in full sun? The answer, in general, is: In our area, they might live but they won't look good. Look for the sun-tolerant hostas at www.hostalists.org, and you'll see a long list, but take the warning that many people who contribute to that list live a good bit further north than we do.
Can I grow hostas in deep shade?
As with the FAQ above, the answer is: not really. Hostas are shade-TOLERANT, but only a few deep green species could be considered shade-LOVING. Deep shade also often means tree root competition or reduced water, which make it even harder for hostas to thrive. In deep shade, try the indestructible H. ventricosa, H. clausa var. clausa, or even 'Undulata Erromena'. It's much better to plant your hostas where they get filtered light (what is known as "high shade"), or where they get 3 or 4 hours of direct sun (morning sun is best) each sunny day.
What are the biggest and smallest hostas?
Because hosta size depends so much on the age of the hosta and its growing conditions, the only relatively comparable measurements are for the hosta leaf size, as these determine into which section the leaf is placed in a Hosta Show.
Can I grow a hosta from a leaf cutting?
Hostas are not like African violets, where you can take a leaf, dip the petiole in rooting hormone, and create a clone. Hostas require some crown (rhizome) tissue to make new roots. (Tissue Culture is a very special case of this.) But if you break off a hosta eye with some crown tissue holding it together, you can, in fact, expect it to grow roots. Rooting hormone helps, and you'll need to support the hosta to keep it upright. It might take two weeks for roots to start forming, during which time you should keep it in deep shade and in constantly moist soil. Indoors would be best.
Can I grow hostas from seeds?
In short, yes. But for a good answer, see FAQ Part III.