Plant shape
Hostas usually reach their full maturity in 4-8 years. Some cultivar can grow up to a couple feet in diameter, Hostas are herbaceous perennially plant that emerge from smalls and develop the leaves at the base of the stems grow into clumps with white-hued plump rhizomes, culture mature hosta forming to dome-shaped mounds flat and even cube-shaped mounds with variety of leave color. They are usually blue, green, or yellow with round to lance shape. Some hostas create mounds in groups, with many different plants clumping together, close to the ground. Vase-shaped hostas have long, slender leaf stalks that curve outward, away from the base of the plant.Hostas bear large, tube or funnel-shaped flowers, generally having six radial lobes that are either white or deep purple. All hosts bloom lily- like attractive flower in summer
Leaf
In their overall contour the leave of hosta difference in leaf’s base and tip
The leaf bases found in different varieties of hostas are in 4 types.

1. Heart-shaped (leaves having two identical, rounded lobes on either side of the petiole or stalk at the point where it goes into the leaf blade.
2. Wedge-shaped (leaves having straight sides, but are converging.
3. Truncate (the leaves appear as if they have been slashed directly through their base.
4. Attenuate (leaves whose sides are arched and converging).

The tip of hostas leaves may IN cuspidate (get thinner gradually and ending at a sharp point), or mucronate (suddenly ending in a sharp point). some type may also be obtuse (rounded) or acute (converging in a point).
The leaf of hostas may be twisted or undulating goes along with the wavy margin some also be cupped. The surface of hostas blade may be dimpled (puckered) or smooth and the puckering might even be minor or deep.
Veins in hosta leave are display the characteristic pattern. When you look at the leaves from above, the veins seem to be susceptible.

Hosta Flower

Hostas are known for their large, lush leaves and mounding forms, but they also have small flowers.the flower will bloom from summer to fall blooming time around 4-6 weeks depend on variety and growing condition because healthy hosta plants bloom more reliably and for a longer than stressed plants
The Hosta always show up in leave bush flower seems to be a second aspect of the Hosta. It can bloom anytime from June to October with funnel or bell shape. Many look like lilies. Hosta flowers come in pink, white, lavender and violet-blue some don’t open at all, most with fine lavender stripe. Some Hosta flowers are fragrant, especially in the evening they will be strong with a scent similar to a cross between daffodil and lily.

 
Hostas Mature Clump size classify

For 5 years growing in ideal condition in same area. Hosta mature will get large clump. When purchasing new plants they will be classified in one of these classifications:

• Dwarf:                  less than 4″ in diameter
• Miniature:             5″ – 9″ in diameter
• Small:                  10″ – 15″ in diameter
• Medium:             16″ – 24″ in diameter
• Large:                 25″ – 36″ in diameter
• Very large:         Over 36″ in diameter

Guideline for size categories by American Hosta Grower Association (AHGA)
Size                          Clump Height                                Leaf Area
Giant                       Greater than 28 inch                   > 144 square inch
Large                      18-28 inch                                      81-144 square inch
Medium                  10-18 inch                                     25-81 square inch
Small                       6-10 inch                                       10-25 square inch
Miniature               Less than 6 inch                            Up to 10 square inch
Based on average mature clump heights (generally 5+ years)
Measurement may vary considerably depending on the age of clump growing condition in America it have simple fact that hosta grow faster in the North than in the South.AHGA (American Hosta Growers Association) set standard for 2 zone of customer that helpful and declare it for customer expectation.

AHGA HOSTA CLUMP SIZE STANDARD Hosta Clump Height
Size                                    North                                         South
Mini                                   up to 8 inch                               up to 7 inch
Small                                 9-14     inch                                 8-11 inch

Medium                           15-22 inch                                  12-18 inch

Large                                23-29 inch                                 19-24 inch
Giant                                30 inch  and above                    25 inch and above