Hosta growers sometimes use some peculiar words (or use words in peculiar ways) to describe their peculiar passions. Here are some you might come across.

Physiology

• Crown The woody rootstock that stores the energy for the dormant hosta. Usually evident in a hosta with 3 or more eyes (see definition below). Hostas are divided by splitting the crown to leave one or more eyes in each piece. Officially, the crown may be called a rhizome, but never a bulb.

• Eye A growing shoot from the crown, supporting 1 (rare) to perhaps 12 leaves. The new eyes are evident as conical projections from the crown in early spring. Also sometimes called divisions, but this is confusing when referring to a plant that has just been divided. Hosta growers will discuss their hosta sizes based on the number of eyes, but recognize that a hosta with 3 small eyes may have less presence in the garden than one with 1 large eye.

• Dormant Eye/Bud These can be seen by careful examination of the crown. Dormant eyes can be forced out of dormancy, e.g., if the main eye is damaged (by predators or a risky technique called Rossizing) or if the crown is treated with a growth hormone like BAP-10. These dormant eyes are what are carefully (surgically) isolated for use in Tissue Culture (TC, see below).

• Petiole The stem that attaches the leaf to the crown. The characteristics of the petiole (flat, winged, etc.) can help in identifying hostas. Hostas with spotted or even purple/red petioles are hot right now, as breeders attempt to carry the red color into the leaf of the plant.

• Flush A set of leaves arising from the eye(s). A hosta may produce 2, 3, or more flushes from each eye during a season. In some hostas, the later flushes will have a slightly different appearance from earlier flushes (e.g., later flushes of 'Undulata' may show hazy green centers rather than the white centers of spring leaves).

• Scape The bloom stalk. Again, the characteristics of the scape can help identify the hosta. Some hostas are known for foliated scapes, meaning that smaller leaves may be attached along the scape (see below). Sometimes hostas that are not known for this do it anyway.

• Pedicel The short stem that connects the flower to the scape. Pedicels are supported by bracts, which may be prominent or small.

• Tepal For hosta flowers, what you may think of as petal. Most hostas have six. A combination of "petal" (inner petal) and "sepal" (outer petal).

• Pod The fruit that forms after the hosta flowers. Usually called "seed pod," but there is "pod parent" meaning the female partner in a breeding pair (the one with ovaries who bears the fruit). Note that some hostas are essentially sterile and may never make pods.

• Tetraploid Tetraploidy is the trait of having twice as many chromosomes as what is "normal." Normally, the pollen provides one set of chromosomes from the male plant (pollen parent), the ovary provides a set from the female plant (pod parent), so the seed has a complete set of chromosome pairs (and so is called diploid). Either by natural or biochemical manipulation of the cells in the plant, it is possible to have plants with two (identical) sets of chromosomes in each cell. In hostas, there is a species which is naturally tetraploid: ventricosa (which has the rare capability to produce seed by apomixis, or asexual means without benefit of pollen). By treatment of tissue cultures, hostas can be "converted" to tetraploidy, but this hasn't been done in hostas as much as it has, say, in daylilies. Tetraploid plants generally have more vigor, substance, larger blooms, etc., but in fact do not often grow as big as their diploid source hosta. (Compare diploid 'Sea Thunder' with tetraploid 'American Sweetheart' at the Hosta Library, for example.) A drawback of tetraploid plants is that the pollen is significantly larger (to hold the extra chromosomes) and so is difficult to use in breeding new hostas. Triploid hostas result from crossing diploid with tetraploid plants, and are effectively sterile. For those of you with unending curiosity, a recent scientific article tested species and cultivars for ploidy.

Descriptors

• Rugose Heavily textured. Also corrugated, bumpy, puckered. Look up 'Lakeside Prophecy'.

• Pruinose Having the waxy "bloom" that makes a hosta leaf appear blue. Some "blue" hostas are better at maintaining this bloom throughout the season (as it can be easily washed off/melted away by heat, water, etc.).

• Cordate Heart-shaped, in reference to leaves. There is also Ovate, meaning oval, as opposed to Lanceolate (lance-shaped) and Elliptic.

• Viridescent Turning green, from gold (as the center of ventricosa 'Aureomaculata') or white (as the center of Whirlwind), as spring turns to summer. Some hostas that emerge gold are simply green by mid-summer (such as 'Chinese Sunrise').

• Albescent Turning white, usually from gold (as the edge of ventricosa 'Aureomarginata').

• Lutescent Turning yellow, usually from green (as the center of 'Gold Standard').

• Substance The weight or sturdiness of the leaves. Good "substance" is often used to imply good slug resistance.

• Fasciated A rare phenomenon where the scapes (see above) are fused into a broccoli-like formation, with a crazy congestion of flowers/buds at the top. Fasciated literally means "bundled." Not to be confused with "foliated" below.

• Foliated Again with the scapes, showing leafy bracts (sometimes referred to as "vestigial leaves") below the flowers. This is typical of some cultivars. For example, the 'Fragrant Bouquet' family will often have a strong leaf or two on the scape. In other cases, perhaps responding to some unspecified stress, the hosta will present a whole bouquet of leaves on a shortened stalk, sometimes even emerging before the spring flush of normal leaves.

• Drawstring A hosta problem where the edge (usually light-colored) of the leaf grows more slowly than the center, making the leaf cup and eventually tear around the edge (think of an elastic shower cap).

• Mini A more-or-less official designation for hostas whose leaves grow to a size ("area" but not really) of less than 6 when you multiply leaf length x width (in inches).

Hosta Health

• Crown Rot One of a few serious diseases affecting hostas in spring. It can be either fungal (Fusarium) or bacterial (Pectobacterium), but the presentation and treatment are similar. The leaves will yellow and droop, and then the petioles will rot off leaving mushy (often smelly) tissue behind. To treat, dig up the plant, discarding (or sterilizing) the soil left behind, clean off any mushy tissue to save what you can, sterilize this clean crown with bleach or other garden treatments (like Bayer 3-in-one), and replant with TLC (that's Tender Loving Care, meaning you might want to pot it up). Often it's too late.

• Edema This isn't just a human condition, it's a plant condition. It happens in spring but the effects last all season. The fresh leaves take on too much water, swelling the cells before the cell walls have a chance to mature. The cells may take on a waterlogged look. Then a change in weather (generally cold spring winds) cause the cell walls to burst, leaving behind damaged portions that look dry and brown. This is what particularly plagues the edges of the classic hosta, 'Frances Williams'. For years, before people understood what was really happening, it might have been called "spring desiccation burn," which unfortunately implies that sun and drought are the culprits; in fact (as described above) it's almost the opposite.

• Hosta Virus X A potexvirus affecting hostas. Visit here for more information.

• Melt-out (or melting out) The problem most often seen with white-centered hostas (e.g. 'Sea Thunder', 'Night Before Christmas'), where the leaf structure (substance) disintegrates, at first perhaps leaving a skeleton of part of the leaf and then disappearing entirely. Caused by fungus, most likely, but difficult to treat or prevent. Use a barrier fungicide or Phyton.

• Nematodes (a.k.a. Foliar Nematodes, or "neems") In hostas these are species of Aphelenchoides that climb onto a leaf (from the ground or from drops of water), poke their way in, and then feed on the tissue between the leaf veins, leaving behind brown streaks that dry out and may completely fall away. That makes this a communicable disease, so growers should be sure their plants are free of neems before selling or sharing. You'll most likely see the effect in late summer in our area, where northern gardeners in cooler climates may mistakenly assume they don't have neems (but they do). Treatment is not easy. Note that these neems are very different from root nematodes (a rarer problem in hostas) and "beneficial" nematodes used for pest control. Some bacterial problems may present a similar appearance.

• Petiole Rot (a.k.a. [Southern] Stem Blight) This, too, causes petioles to "rot" away from the crown, but is more commonly seen in humid summers, not in spring. This is a fungal disease caused by Sclerotium rolfsii, which will leave behind white stringy material and sometimes orange "mustard seed" fruiting bodies on the rotting stem. Treat with fungicide, and be sure not to have mulch piled up against the base of the hosta.

• Sun damage Yes, hostas can be damaged by heat and too much sun. Blue hostas will lose the crystalline waxy coating that keeps them blue. In the extreme, leaves can look burned. Don't confuse this with other damage. See the picture at left, where cutting back some trees led to this damage on a blue hosta (which got too close to the ceramic ball at left, causing leaf burn).

Mutations and hybrids: where new hostas come from

• Sport A mutation from a mother plant, hopefully to something more interesting! Sports usually denote a change in leaf color/form ('June' is a sport of 'Halcyon'), but may refer to different flowers as well ('Aphrodite' is a double-flowered sport of plantaginea). Sports may arise on hosta clumps of any size, but are nowadays a very common by-product of Tissue Culture propagation (see below).

• Reversion A mutation back to the original seedling form, whether that form was variegated or not. A streaked sport will often be unstable, and revert to the margined or plain-colored form. Avoid using "revert" when a variegated plant has sported to a solid color, unless you know that is the original color. Even then, solid color sports may be different in some subtle way from that "grandparent" form.

• Seedling I'm including this definition here for comparison to sport. All hosta cultivars were once seedlings, even if that seedling arose a very long time ago (as for H. 'Undulata'). Most seedlings are solid color, unless they came from a streaked seed pod (usually from a streaked breeder, see below). Any variegation arises from mutation (sporting) from the solid color, or from stabilization of a variegation pattern from a streaked seedling. 

• Hybrid A seedling from crossing parents of different genetic heritage. For hostas this generally means that there is mix of species involved, although many early hostas arose from crossing selected species forms with each other. A "selfed" hybrid is one where the flower was self-pollinated. Bees are good at this! Even so, the seedlings from a selfed hybrid will not look exactly like the parent plant.

• Streaks Some hosta seed-grown plants or sports may show streaked variegation, which is exactly what it sounds like. These streaked plants are unstable, and will mutate to one or more "stable" forms, usually with variegation (light edges or light centers).

• Streaked Breeders In a breeding program, streaked plants are valuable because as pod parents they can pass on streaked properties to their offspring (usually resulting in stable, variegated plants). Note that without a streaked pod parent, your chances of obtaining variegated offspring are extremely low. Streaked plants tend to be expensive, one-of-a-kind plants that must be maintained by frequent division to retain the streaking, if that is the goal.

• Weedling What gardeners might call the chance seedlings that show up in the garden, usually OP hybrids (see below).

• Also see the Hosta Naming page for explanations of species, cultivars, etc.

Abbreviations

• TC: Tissue Culture Production of large numbers of test-tube baby hostas, beginning with only a slice from the crown of a plant. "TC Liners" are these babies, just big enough to plant out into nursery 6-pack planters. "First year TC" are a bit beyond that, perhaps at the end of one season's growth. The younger the TC plant, the greater likelihood that you can't be sure you're getting a carbon copy clone of the original.

• OS: Originator's Stock At first (in the days of yore before tissue culture) this meant that you could easily trace your plant back to the original named plant, preferably with as few steps in-between as possible. Nowadays, it just means that you can positively state that the plant never went through a tissue culture stage (i.e., there is an O.S. chain there, even if you can't trace it exactly). Many people think that's worth some extra $, as you can be more assured of the stability of the genetics.

• OP: Open Pollinated This distinguishes controlled pollen crosses—where the breeder transfers pollen from one flower to another whose stamens have been removed—from uncontrolled "open" ones—where the flower either pollinated itself or a hybrid was created by insect activity (hosta pollen is too heavy to move about by wind).

• NOID: This isn't just a hosta term. It means "no identification" (as in "What's my name?"). If you have NOIDs in your garden, you might want to check this page.

• HVX: Hosta Virus X A potexvirus affecting hostas. Visit here for more information.

• BME: Blue Mouse Ears This popular mini (or is it? see above) gets its own abbreviation. Other less common abbreviations are OMT (One Man's Treasure) and IAT (Ice Age Trail), both common in breeding programs.

 

For the much longer AHS dictionary of terms, click HERE.