Do the Limbata

Here’s an image taken this month of the wonderful Aucuba japonica ‘Limbata’. While most aucubas have yellow leaf specks, this old cultivar, first mentioned in historical literature in 1864, is sadly still quite unknown in gardens. That’s not too surprising, however, due to its slow production time as a commercial nursery crop. For dry shade in Zone 7a-9, this wonderful broadleaf evergreen is hard to beat.

Winter flowering Strawberry Tree

There aren’t a large number of trees that flower in winter in temperate climates, but one we can’t imagine gardening without is Arbutus unedo ‘Compacta’. This amazing Mediterranean native has thrived for us since the late 1980s.

Arbutus is a member of the  Ericaceae family, which is why the flower so closely resemble those of its cousin, Pieris.

The clusters of red fruit that ripen in late winter after months of flowering resembles miniature strawberries, hence the common name of strawberry tree. The shaggy cinnamon bark is also another striking ornamental feature. Our 30 year old specimen has reached 12′ tall x 12′ wide. Hardiness is Zone 7b and warmer.

Arbutus unedo ‘Compacta’
Arbutus unedo ‘Compacta’
Arbutus unedo ‘Compacta’ bark

Kaizuka! Bless you.

I first met Juniperus chinensis ‘Kaizuka’ on a mid 1970s student field trip to Florida with the late JC Raulston. As our caravan of University vans crossed from Georgia into Florida, these junipers suddenly appeared everywhere. Although, I was unfamiliar with this architecturally fascinating specimen, I was in love….despite it being common as the proverbial dirt in Florida landscapes. Everywhere from gas stations to the poorest home seemed to have at least one. Most locals know Juniperus ‘Kaizuka’ as either Juniperus ‘Torulosa’ or Hollywood Juniper…a common name it gained due to its ubiquitous presence around Los Angeles. It turns out that Juniperus ‘Kaizuka’ was an introduction from Japan’s Yokohama Nursery prior to 1920. Our oldest plants at JLBG are now 33 years old, and now measure 24′ tall x 16′ wide. The one pictured below is a new 5 year old planting in a new section of the garden. Forty-five years later and still in love!

Grapefruit time in the garden

We love December, since that’s when the grapefruits start to rain down from our xCitroncitrus ‘Dustan’ tree at JLBG. Few people who come to the garden actually look up enough to notice this fascinating plant. xCitroncitrus ‘Dunstan’ is a bigeneric hybrid between the hardy trifoliate orange, Poncirus trifoliata and a grapefruit. The result is a winter hardy fruit that’s pretty darn close in size, taste, and appearance to a grapefruit. To be technically correct, the fruit is known as a Citrumelo. Whatever you want to call it, it’s pretty darn cool to be harvesting hardy citrus here in Zone 7b. Last year, we harvested over 3 dozen fruit off our single tree.

Only the Green Shadow Knows

Here’s one of our favorite hollies, looking great in the garden this week. Ilex integra ‘Green Shadow’ is a variegated (creamy-edged leaves) form of the Mochi holly. This amazing columnar holly, that hails from oceanside mountain slopes in Japan, Korea, Southern China, and Taiwan, reaches 20′ tall x 7′ wide, which is the case with our 16 year old specimen. Although Ilex integra ‘Green Shadow’ will grow in both sun and shade, full to half day sun results in the most dense foliage. This is female clone, but we never see more than a dozen berries, so we assume it needs a male nearby to fruit better. For a narrow evergreen screening plant, it’s hard to beat. Hardiness is Zone 6b-9b.

Selective Love

I’ve never been a huge fan of nandinas in the garden. I find the more typical forms very difficult to integrate from a design perspective, and I find the popular Nandina ‘Firepower’ to be near the top of the list of most grotesquely ugly plants used in American landscapes. Yes, it’s colorful, but the plant lacks any grace, and has the form of a pile of wet red Kleenex.

Of the older cultivars, I like Nandina ‘Harbor Dwarf’, with it’s low spreading form, but the paucity of fruit keeps most people from planting it. The only downside for us is that it spreads to cover a very large footprint, so can choke out other nearby plants. We continue to trial all of the new nandina introductions to see if anything strikes our fancy.

My favorite member of the genus, which I first met at the JC Raulston Arboretum back in the 1980s, is Nandina domestica ‘Filamentosa’. This cutleaf, slow-growing, non-fruiting selection from Japan is often marketed under the trade name San Gabriel. It adds a distinctly Japanese flavor to the landscape, which is why we planted a mass in our new Japanese garden. Here is a photo from this week with it’s lovely rosy winter color. Winter hardiness is Zone 6b-9a.

Narrow-leaf Sweet Box

Sarcococca saligna is one of our favorite species of sweet box, but sadly one of the most tender. If winter temperatures drop below 10F, it dies to the ground, but has always resprouted. When we have mild winters, it becomes an extraordinary woodland garden specimen as is evidenced by this current photo.

Fall Fatsia Flowers

Here is the wonderful Fatsia japonica ‘Variegata’ in our garden on Oct 25. This fabulous shrub is a member of the aralia family, and a first cousin of the off-despised running ivies. Not only do we love Fatsia for its amazing bold texture and evergreen foliage, but we love it because it flowers in fall. The second photo was taken a mere four weeks later, when it had exploded in full bloom.

Fatsia japonica ‘Variegata’
Fatsia japonica ‘Variegata’

Fatsia japonica is a superb pollinator plant at a time when so little is in full bloom. Our winter low temperatures so far have been 27 degrees F, which hasn’t affected the flowers. Winter hardiness is Zone 7b and warmer.

Fatsia japonica ‘Variegata’

A New Ironwood earns its mettle

It’s far more common for new perennials to be discovered than new trees…it’s a size thing. Botanists were excited in 1960, when Chinese professor H.T. Chang published a new small tree that he thought to be a witch hazel, named Hamamelis subaequalis. The original Jiangsu Province collection actually dated to 1935, but it took 25 years to be published based on a herbarium specimen of the fruit.

The new hazel hadn’t been seen alive since 1935, and was assumed extinct, when it was rediscovered in 1988 by a team from the Jiangsu Institute of Botany. After studying live flowering specimens for three years, it became obvious that It wasn’t a witch hazel at all, and a new genus, Shaniodendron was published for the plant. Here, it remained, until 1997, when DNA analysis revealed that Shaniodendron was actually a second species in the formerly monotypic genus Parrotia….only living some 3,500 miles from its nearest relative. Its sibling is the famed Iranian Ironwood (Parrotia persica).

Currently, there are only five known populations in China, so it is quite rare in the wild. The largest plants seen in the wild were 30′ tall, but Parrotia subaequalis should grow slightly taller in cultivation. The photo below is our 13 year old specimen. Most plants of Parrotia subaequalis in the US, including our specimen pictured below, trace back to famed Japanese plant collector of Chinese plants, Mikinori Ogisu. Fortunately, Parrotia subaequalis is quite easy to root from cuttings, so we hope its not long before this amazing plant becomes much more widespread in commerce. In trials so far, it came through -25 degrees F with only slight tip damage, so it looks like a solid Zone 5-8 plant.

Washington’s Palm ready for winter

Due to having three consecutive mild winters, with no temperatures below 20 degrees F, we’ve actually been able to get a trunk on our Washingtonia filifera palm. Typically not hardy in our climate, our plant was grown from seed collected from a wild population in Arizona that had experienced 10 degrees F. We’ll see what this winter has in store.