Gardenesque

Hollies for Clay Soil . . .

Short List of Hollies for Clay Soil

In the table below are Hollies that perform well in clay soil in our area. The table includes the basic information needed to help you site these plants properly. It also includes information on deer resistance and rabbit resistance. So far, I haven't seen deer in my garden and the deer information is from various sources that I have collected over the years. The rabbit resistance information is based on my own garden experience as I always seem to find plenty of rabbits in my garden. Here's how to interpret the information:

For both Deer Resistant and Rabbit Resistant headings:

• yes - the plant is not usually eaten. It's possible, though, in some years the pest may eat the plant.
• no info - there is no definite statement as to the plant's resistance.
• no - the plant is eaten.
• favorite food - the plant is definitely eaten.

Light Requirement heading:

• sun - 6 or more hours of direct sun each day.
• pt sh - up to 6 hours of direct sun each day.
• sun to pt sh - must have some direct sun each day. Flowers better in more direct sun.
• shade - no direct sunlight.
• pt sh to shade - less than 6 hours of direct sun to no direct sunlight.
• sun to shade - will grow in any amount of light.

Soil Requirements heading:

• moist - soil does not dry out quickly.
• organic - soil has leaf mold or compost or other organic amendment.
• well drained - soil does not remain soggy and rot the plant's roots.
• infertile - opposite of organic - lacking soil amendments.

Hollies and their Cultivars

Hollies are very attractive plants with glossy, dark green leaves and a pyramidal habit or rounded shape. They are one of the workhorses in the landscape or garden because most have evergreen foliage and can be used to build the bones or background of the garden. Some work best in shady spots; others in sun. The ones listed here do well in clay soil. As their flowers are dioecious; that is, male and female flowers are on separate plants both male and female plants need to be planted close to each other to have berries on the female plants. But this isn't always needed as I have discovered and noted below.

Pollination Question -- I've had several questions as to the maximum distance for male and female plants for proper pollination. My research shows about 100 feet is the maximum distance.

Culture -- Hollies usually require moist, acid soil. Most soils in Harford County are in the proper pH range to grow them. They grow in sun to part shade and some will even grow in shade. Most prefer well-drained soils but some will take standing water as mentioned in the next article on this page.

Uses -- Depending on their size, hollies can be used in a variety of ways. Some of their uses are in foundation plantings, at house corners, as screens, hedges, accents in beds and borders that don't have high pH plants in them, in boundary plantings, in masses, and, most important, as specimens.

Here's a list of holly species, their cultivars, and crosses that grow well in this area. Most of these I have either grown and enjoyed, or have watched them grow and prosper over the years in my community or in nearby gardens.

English Holly - Ilex aquifolium

English holly is a slow-growing, pyramidal tree growing to about 30x20ft. Its leaves are glossy, dark green with spines; berries on female trees are usually red except for a few cultivars that have yellow berries. They require acid, well-drained soil. The English holly will grow in sun to part shade. It tolerates severe pruning so it is a good plant for formal hedges and topiary. I think it is beautiful grown to its full size with its lower branches sweeping over a beautiful green lawn–-the perfect lawn ornament. Use it in groups or as a specimen. If berries are wanted on the female holly, a male must be planted as well. English Hollies are suitable for planting in USDA Zones 6b, 7a, and warmer. The English holly is not as hardy as Ilex opaca in this area. Some cultivars are:

'Angustifolia' is a female with narrow foliage and compact, pyramidal habit. It has dark-green, narrow leaves, dark purple stems and red berries. It is slower growing than the species. Grows to about 6 ft high. This holly will grow in USDA zones 6a and warmer.

'Argenteo Marginata' is an upright, female plant with gold variegated foliage. Produces abundant bright red berries. This holly will grow in USDA zones 6b and warmer. Grows to 20x12ft wide.

'Argentea Marginata' is very similar to the above 'Argenteo Marginata' holly except that its leaves are edged in silver.

'Little Bull' is a male holly with small foliage and grows to 15ft.

'Siberia'(‘Limsi') is a small-growing holly to 15x6ft. Has lustrous, deep green foliage and contrasting red berries. Matures to a dense, narrow, cone shape. Because of its small size, this holly can be used for the corners of a foundation planting or as a hedge.

Chinese Holly - Ilex cornuta

Chinese holly is a medium-growing, rounded shrub growing to 10x10ft. It is listed as growing in USDA Plant Hardiness Zone 7. Since most of us live in Zone 6B which is a little bit colder, it would seem that it is not used in this area but I have seen it used often in foundation plantings. Its spiny, dark green leaves are very prickly and have been described as "lethal". The female has red berries. This plant does best in moist soil in sun to shade, but it is very tolerant of dry soil. The Chinese holly is easily pruned to almost any size. Michael Dirr in his "Manual of Woody Landscape Plants" calls the Chinese holly an "iron-clad, bullet-proof plant" for Zone 7 and protected areas of Zone 6. I would not recommend the species for the northern parts of Harford County above Bel Air, and I don't use it in my designs. It is here because it's been used in hybridizing work making new hollies that are very popular.

'O. Spring' - Pamela Harper in her book "Time Tested Plants" recommended the cultivar 'O. Spring' as a beautiful irregular-upright form with cream-colored leaves. It's male and does best in part shade. It grows to 10 feet high but can be pruned to any size.

Japanese Holly or Box-leaved Holly - Ilex crenata is an evergreen shrub or small tree native to eastern China, Korea and Japan. The leaves don't have spines. There are separate male and female plants, but since the fruits are black there is not much need for having both male and female plants. Like all hollies it grows in acid soils. This genus is hardy from USDA zones 5 to 8. The Japanese holly comes in many shapes and sizes from small to large and from fat to thin as you can see below. It's used a lot in foundation plantings. Here are some that I think are worthwhile for your garden:

'Compacta' (aka ‘Bennett') is a dense, well-branched shrub with small, spineless, dark green leaves. The female plant produces black berries. It prefers moist, well-drained, acid soil. It grows in sun to shade and withstands heavy pruning. Grows to 4x4 feet and more if left unpruned. Japanese hollies are used in foundation plantings, as accent plants, hedges of short and medium height, and in masses.

'Soft Touch' is a dense, mounded, evergreen shrub with soft-textured, glossy green leaves that have an interesting silver mid-vein. Grows to 2-3 feet wide.

'Chesapeake' has a pyramidal form so it is often used in foundation plantings. Grows to 7x4ft and has lustrous, dark green leaves. There are also ‘Steeds' and ‘Nigra' with pyramidal forms. I think ‘Nigra' is the best looking of the three because of its lustrous, dark green leaves and tight form.

'Helleri' grows slowly to 4x5ft and has a horizontal, mounded look rather than rounded. Has flat green leaves and is supposed to be a female but I've never seen berries on one.

'Sky Pencil' is very slender and densely branched, growing to about 8x3ft, and provides a nice exclamation point wherever needed. It has lustrous, dark green leaves and is female.

'Hoogendorn' is a low growing, densely branched, compact evergreen shrub with flattened, dark green foliage. It is similar to boxwood and is a male plant so it does not produce berries. It grows to 2x4ft and looks like it can be grown as a ground cover.

'Kingsville Green Cushion' has a very low-spreading form and is female. Grows to about 1x2ft in 10 years. This Japanese holly is often used as a replacement for boxwood for edging in formal garden layouts.

'Golden Gem' - has golden-green leaves and is a small growing cultivar. Grows to about 2x4ft and has a low, spreading habit. It colors best in sunny spots so it will lose its golden glow in shady areas.

‘Snowflake' is an upright growing holly with beautiful white and green variegation and is a female. It's very nice in a shady spot.

Inkberry Holly - Ilex Glabra

Inkberry holly is a native, evergreen holly slowly growing to an upright-to-rounded 8 feet shrub. The spineless leaves are dark green and the females produces black berries. Inkberries prefer moist, acid soil in sun to shade. In its native habitat it is often found in swamps so it can be grown in wet soils. With the interest in using native plants in our landscapes and gardens and the fact that Ilex glabra will grow where no other holly will grow, it is now much easier to find at nurseries. It takes heavy pruning well and can be used in wet soil, dry soil, sun, or shade. Inkberries are easy to spot in landscape plantings because they naturally loose their lower foliage.

'Ivory Queen' has ivory-colored fruit and is supposed to keep its lower leaves better than the species. It grows to 6x6ft.

'Compacta' has denser foliage than the species but can grow just as large.

'Shamrock' has lustrous, dark green leaves and is more compact than the species growing to 5x5ft.

American Holly - Ilex opaca

Ilex opaca is our native, upright American holly growing slowly to 40x20ft. Its olive green leaves have spines and the females produce red berries. The American holly prefers moist, well drained, acid soil. It prefers sun to part shade conditions. Ilex opaca can be used in the same ways as the English holly. Use cultivars rather than the species because the cultivars have better leaf color and better berry production. The lower branches of the American Holly also grow so they sweep the ground and produce a majestic picture--the perfect lawn ornament. Just a few of the available cultivars are listed here:

'Baltimore Buzz' is a male holly hybridized by Bill Kuhl of McLean Nurseries in Baltimore.

'Miss Helen' has a broad pyramidal form with red berries in winter and dark olive green leaves. This tree forms a dense pyramid and grows to 40x20ft.

'Satyr Hill' is an introduction from McLean Nurseries. She has plenty of glossy, dark red berries and a very dense, pyramidal form.

'Dan Fenton' - Dr. Elwin Orton is a holly hybrider who works at Rutgers University and he recommends several American hollies. One is Ilex opaca 'Dan Fenton' which has dark-green, glossy foliage and abundant bright red berries. It grows to 35x20ft. He also recommends the following:

'Jersey Knight' is a male holly with excellent foliage and leaf color. It is narrow and conical in form.

'Jersey Delight' is a female holly with very shiny, dark green leaves and makes a nice conical form. It fruits heavily and displays its fruit very well.

'Jersey Princess' is said to be the best of the Rutgers releases because of its lustrous, very dark green foliage and abundant red fruits.

Winterberry Holly - Ilex verticillata

Winterberry holly is a deciduous holly with spineless, dark green leaves. It's grown for its beautiful red berries that show so well after the leaves drop in the fall. The berries produced on female plants usually last through the winter season. The species grows slowly as a shrub to 10x10ft in a rounded form. Winterberry holly requires moist, acid soil. This is another of the hollies which is found in swampy areas and will grow in wet soil. Plant it as a specimen, in groups, or beside water features.

There are two groups of female Winterberry hollies: early flowering and later flowering. When purchasing a female, a male plant that flowers at the same time must be purchased too. 'Jim Dandy' is an early flowering male, 'Southern Gentleman' is the later blooming male, and x 'Apollo' is the male for the hybrids mentioned below.

Early Bloomers: ('Jim Dandy' is the pollinator)

• 'Afterglow' is a compact grower to 8x5ft and has red-orange berries.
• 'Aurantica' is another compact grower to 5x3ft and has red-orange to yellow-orange fruit.
• 'Red Sprite' is small growing as well to 5ft high with persistent, bright red fruit, and lustrous dark green leaves.

Late Bloomers: ('Southern Gentleman' is the pollinator)

• Winter Red® is, according to Michael Dirr, the best fruiting Winterberry holly. It grows to 9x8ft and its large, bright red fruits are visible into February.
• 'Winter Gold' is a sport of Winter Red® and has yellow fruit.

Hybrids (crosses made between Ilex verticillata and Ilex serrata)(x ‘Apollo' is the pollinator)

• x 'Sparkleberry' is an upright growing holly with brilliant red fruits persisting into March.
• x 'Bonfire' has masses of bright fruits that ripen early with its branches drooping from the weight of the fruit. This plant fruits at an early age and can grow to 10x10ft over time.
• x 'Harvest Red' has bright red berries and lustrous, dark green foliage.
• x 'Apollo' is the male hybrid to be planted with these hybrids for good berry production.

English Holly Hybrids

• 'Carolina Sentinel' is a dense, narrow pyramidal plants with lustrous dark green leaves and bright red berries. Grows to 20x5ft.
• 'Brilliant' grows to a 20ft cone and has abundant fruit without pollination.
• 'September Gem' is a 10 ft pyramid with leathery, dark green foliage and red fruit.

American Holly Hybrids - Here is an important group of hybrids between Ilex cassine x Ilex opaca:

• Ilex x attenuata 'Fosteri' - Foster's hybrid hollies - has small, lustrous, leaves with a compact, pyramidal habit. Abundant fruit persists through winter. Grows to 25x10ft.
• Ilex x attenuata 'Fosteri' - The Foster's hybrid hollies are a little different in their nomenclature as they are numbered from #1 through #5. Foster's #2 and #3 are the best females. Foster's #4 is a male plant. Foster's #1 and #5 are inferior and should not be purchased. I don't think they would be available in the retail trade anyway.
• 'Longwood Gold' is a dense, pyramidal form with dark green foliage and golden yellow fruits. It is a knockout tree! There are so many fruits on this tree that the plant looks yellow and not green. Longwood Gardens developed this plant and will be selling it in the future.
• 'Sunny Foster' - similar to Foster's #2 except its new foliage is yellow and then fades to green. It has red fruits.

Meserve Hybrid Hollies - Ilex x meserveae

Meserve Hybrid Hollies, are a group of shrub-type hollies with beautiful, glossy, spiny, dark green leaves and purplish new stems. The females have bright red berries. They are the result of crossing various hollies including Ilex aquifolium, Ilex cornuta, Ilex rugosa, Ilex pernyi, and others. They all require moist, acid, well-drained soil. They grow well in sun to part shade except that the blue-leaved hollies should be planted in part shade. Also, I have seen the blue-leaved hollies burned by the hot, western sun. Most of these cultivars are susceptible to summer droughts and should be watered on a regular basis. The blue hollies need moist soil and at least part sun; otherwise they will be short-lived plants. As with most other hollies, they take hard pruning well. Some of the most popular of the Meserve group are:

• Ilex x meserveae 'Blue Angel' - Blue Angel® has crinkled, glossy, dark, bluish-green foliage with large, shiny, deep red fruits. It is the slowest growing of the female Meserve hollies and grows to 8x8ft.
• Blue Maid® ('Mesid') is a larger, fast-growing holly with pyramidal form, red fruit, and dark, bluish-green foliage. Grows to 15ft high.
• Blue Prince® has dark, bluish-green leaves and is a male. It is dense and broad spreading and is supposed to grow to 12 feet high but I've never seen any this large. It is one of the hardiest of the Meserve hollies.
• Ilex x meserveae 'Blue Princess' - Blue Princess® has dark, bluish-green leaves and bright red fruit. It is dense and broad spreading and grows to 12 feet high but, again, I've never seen any this large.
• Blue Stallion® (‘Mesan') has dark, bluish-green leaves and is a male. This one doesn't have spiny foliage. It is a good pollinator for the other blue-leaved hollies as it flowers over a long period in spring. It is large growing to 15x10ft.
• China Boy® (‘Mesdob') has dark green, spiny, glossy foliage, yellowish new stems, and is the pollinator for China Girl.
• China Girl® (‘Mesog') has dark-green, spiny, glossy foliage with yellowish new stems, and is a female plant. Again, it is dense and broad spreading. As it takes hard pruning it can be kept to just about any size. Both China Boy® and China Girl® have excellent heat tolerance because one of their parents is the Chinese holly - Ilex cornuta.
• Dragon Lady® ('Meschick') makes a very narrow pyramid to 15x4ft and has spiny, lustrous, dark green leaves. Use it in a hedge, as an accent plant, or in foundation and corner plantings. It is a female producing bright red fruit. I've grown this plant for ten years and it sets lots of fruit but the berries fall off before turning red. Maybe it's not getting enough water.
• Golden Girl® (‘Mesgolg') has a broad pyramidal habit and dense, dark green foliage with yellow to orange fruits.
• Ilex x meserveae 'Honey Jo' is a variegated sport from a Meserve holly. This is a slow-growing plant with yellow and green variegated leaves. It grows to 4x4ft and bears red berries. This is a lovely plant and works out very well in part shade.

Various Hybrid Hollies:

• Ilex x 'Nellie R. Stevens' is a hybrid between Ilex aquifolium and Ilex cornuta. It grows quickly to about 20x15ft in a broad, pyramidal form. It has large, shiny, spiny, quilted-looking leaves and large, red fruit. It can be pollinated by a male Ilex cornuta. There are many lovely specimens growing in the community where I live and it's a pleasure to walk with my dog during the winter and enjoy their bright, red fruits (they all seem to fruit heavily), and their beautiful form. They are very dense plants. Use them as specimens, at lot corners, boundary markers, and hedges. Don't use them in foundation plantings because they grow too large. They require moist soil and need sun to part shade.
• Ilex x Red Beauty ('Rutzan') is a new 8' holly (photo to right) that combines glossy, dark green foliage with an abundance of bright red berries. It becomes densely branched with a narrow conical form without any pruning needed. Any Ilex x meserveae male is a suitable pollinator. This is a Dr. Orton introduction and he says that it will be a very important cultivar in the future because of its beautiful form. We purchased several of these plants and, even though they are still small, I can see that they will have great form without pruning.

Yaupon Holly - Ilex vomitoria

Yaupon holly is not normally for sale in this area as it is listed as a Zone 7 plant, but I find it in lots of gardens, including mine, even though I didn't plant it. The birds are usually the culprits by dropping the seeds. It is upright to rounded in form and grows to perhaps 20 feet tall. Its spineless leaves are a shiny, dark green; fruit is a bright red. This is an adaptable plant living in soils from dry to wet. It can be used as informal screens, hedges, masses, and foundation plantings.

• 'Xanthocarpa' is a yellow-fruited cultivar listed in the Forest Farm catalog.

Some Additional Notes -- Except for the Yaupon holly, all these hollies are great for use in the Harford County area. They will survive in clay soil as long as the clay drains well. All do well in sun to part shade. I don't think that any of the hollies like the hot, western sun. I would not use any holly in a very windy location as the wind may discolor their leaves in winter or even defoliate them. If they are properly sited they will make beautiful specimen plants.

Don't let the spiny leaves stop you from planting hollies. Wear gloves while handling these plants and all plants for that matter. The new growth on most of the hollies is soft enough not to scratch you.

In drought conditions, like all other plants, hollies suffer from insect infestations. It really is important to take the time every 3 or 4 weeks during drought periods to water them deeply and give them a good cleaning with a hard spray of water which will often remove any insects and their webs.

One holly species that is not listed here is Ilex x koehneana or Koehne Holly. It's a Zone 7 plant. I've seen several hollies surviving in our area but I don't think there are enough of them in various sites to say that it is really hardy in our area. They have lustrous leaves that are larger than either the American or English hollies and they are gorgeous but it is too soon to make a judgment.

Many of these hollies are available in small sizes from McLean Nurseries on Satyr Hill Road in Baltimore. See my article about McLean Nurseries on my Local Nursery Page. Bill Kuhl, owner of the nursery, has planted specimens of some of the plants he carries. You'll also find many other hollies at his nursery that aren't listed here.

Holly leaves and berries are toxic and should not be eaten.

Hollies for Poorly Drained Soils

A study performed recently analyzed the ability of certain hollies to withstand having their roots under water for eight weeks. These same hollies were also assessed for plant survival the winter following the flooding. These six hollies performed the best and had 100% survival rate:

• Ilex x 'Nellie R. Stevens' or Nellie R Stevens holly
• Ilex cornuta 'Burfordii' or Burford Chinese holly
• Ilex glabra or Inkberry holly
• Ilex x meserveae 'Mesog' or China Girl® holly
• Ilex verticillata Winter Red® or Winter Red winterberry
• Ilex x attenuata 'Fosteri' or Foster's hybrid holly

The two hollies in the next list performed almost as well as shown by their survival rates noted as a percentage after their names:

• Ilex opaca 'Satyr Hill' or Satyr Hill American holly - 95%
• Ilex crenata 'Convexa' or Convex leaf Japanese holly - 90%

The following two hollies, though, performed very poorly as shown by their survival rates:

• Ilex x meserveae Blue Princess® - or Blue Princess holly - 40%
• Ilex aquifolium 'Monler' or Sparkler® English holly - 6%

This study suggests that the first six hollies can survive being flooded for up to at least eight weeks. The inkberry holly and winterberry holly do prefer moist sites and should survive in wet sites. The percentage rates on the last two hollies with survival rates of 40% and 6% show that they need well-drained soil year round and should not planted in poorly draining soil.