August 30, 2012

The Beautiful Blue Marble Tree

Blue Marble Tree seeds

I have a rare and delightful job as a horticulturist in a public garden, in which I can grow a great many species of plants. I can also experiment with new species, trialing them for planting in the local area. One such experiment has been modestly successful so far, with the Blue Marble Tree. This majestic tree has a lot of good qualities as a large  tree, but only the coming years will show if has longevity, sturdiness and the other attributes which make a good "landscape" tree versus a specimen for a garden or street tree. 

Blue Marble Tree flowers

The botanical name for this tree is Elaeocarpus grandis, one of dozens of species in the genus, all of which are tropical or subtropical, all are Old World, most are from from Asia and the Indo-China area. One other species, E. decipiens, The Japanese Blueberry Tree, is a bit more common in the landscape trade in Florida where it shows a lot of promise as a street or courtyard tree. It is of modest size, has a well-rounded crown and seems trouble-free after about 15 years in cultivation in Florida and other states. 

Marble Tree foliage;
older leaves turn scarlet
   For the larger E. grandis, the tree will easily grow to 50 feet or more, and has both brilliant red senescing leaves as well as deep green foliage, set against a very dark straight trunk. The trees are fairly hard to come by, but are worth the cost and time to locate them. We are fortunate to have gotten some seed from a tree I planted here in 2005 and the seedlings are already 7 feet tall after 18 months. I look forward to planting them in the Gardens as well as other parks in Pinecrest next Spring. The trees are undemanding in their culture, but do like regular watering and plenty of sunlight. The seeds are fickle regarding germination; they can take 4-12 months to sprout even with  bottom heat and scarifying the seeds.

There are hundreds of tree species available for planting in this area of the country, and I hope to some day see a few dozen Blue Marble Trees dominating the treescape, their canopies stretching up and over their competitors. The effect would be compelling; the foliage and stature of the tree merit a closer look at planting them in parks. Their very tall growth precludes their use as a street tree in the event of a storm, they would eclipse an entire road. The next decade holds exciting new introductions for this area. Consider a Blue Marble Tree for your garden if space and climate permit planting one. 

Craig Morell
Pinecrest Gardens    

August 13, 2012

Dyckias: Not Bad.......Just Misunderstood

The magnificent Dyckia 'Cherry Coke'

In some ways, bromeliads are like cactus: people only remember the spines, and overlook the benefits; even a thorny plant can have the reward of beautiful flowers. Such, I believe, is the case of the often-feared Dyckia group of bromeliads. For many people, looking closely at a well-grown Dyckia is usually cause for a wincing look or perhaps a long pause, followed by a cautious distance from the plant. Yet, in the nursery at Pinecrest Gardens, we bare-hand Dyckias without bloodshed or fear; we've learned how to stay clear of the spiny parts. The teeth of this plant group are no more dangerous than a carpenter's saw, and just as stationary; know where the teeth are, and stay away from them. My college mentor in Gainesville would have given me stern counsel: "you know about the danger, so deal with it ! Don't use it as an excuse to stay away from the plant, just work around it."

Dyckia 'Brittle Star'

As with cactus and succulents, you learn to stay away from the sharp parts, and learn patience when maintaining the plants in the ground or in pots. A few specialized tools will help in removing debris and weeds amongst the teeth, but in reality, the teeth of these plants are more fearsome looking than actually sharp.

On the contrary, I've met some some cacti that I truly believe have the ability to reach out and grab you from several feet away, using some level of diabolical plant intelligence. Dyckias are less menacing, and if you pick up potted plants from underneath, you'll find that the plants aren't as fearsome as they look. Dyckias have all the feel and look of being succulents, and many come from rather hostile native habitats, just like succulents or cacti.  

the beautiful and oh-so-silver
D. marnier-lapostollei
One of the most surprising aspects about this group of plants is that they like more water and larger pots than the conventional dry succulent /cactus culture dogma might call for. I failed with growing Dyckias for years until my great friend Mike McCaffery in Gainesville kindly reminded me that Dyckias hadn't read the books about how succulents should grow; they instead prefer to grow fairly well-watered and well fertilized. In such conditions, Dyckias grow rather fast, and send up beautiful flowers which do a grand job of attracting hummingbirds. 

D. 'Moonglow'
from Yuccado Nursery

D. platypoda flowers,
indicative of the style and color
of the genus

 The flowers are usually very bright colors, often yellow or orange, on 3-7 foot tall spikes, some of which are branched. The plants often set seed easily, and the seed is fairly easy to sprout. The major problem in getting pure strains of seed is out-crossing between species if several species have open flowers at one  time. There are plant sizes for every size of landscape or plant collection, from miniature plants a few inches across to giants as large as a wheelbarrow. Some species are hardy to USDA Zone 7. Once again, we have a plant group with  wide diversity in growing conditions and plant sizes available for you to grow. I wonder how many readers knew of this group, and how many have actually grown some of the species ?

long surgical hemostats useful for
weeding amongst spiny plants

a not-so-secret weapon
to remove weeds around Dyckia plants

Craig Morell
Pinecrest Gardens


August 9, 2012

Salvias for Every Landscape
or ...Sage Advice....

For decades, gardeners in almost every state in the country have planted Salvias to brighten their gardens. As a teenager in Milwaukee, I remember planting the most common red annual variety of annual Salvia, carefully pinching the tops off to make more flower heads, watching the plants grow and set seed, then die at the first hard frost of Fall. I had no idea then that so many varieties of this genus existed, much less their potential in the landscape as perennials. I had to move to Florida before I discovered different varieties of Salvia, and was amazed to find that some species can grow to the dimensions of a small garage. On the other side of the size spectrum is the Florida native Salvia coccinea ,    a petite species growing to 2 feet, with dainty pink-white or red florets.

S. guaranitica

One of my favorites is a gorgeous perennial blue-flowered variety called S. guaranitica, which can easily grow to 4 feet in height. The species attracts winged wildlife of many sorts, especially bees and butterflies. The Forsythia Sage, S. madrensis, can grow to 6 feet tall by 8 feet across, and is topped off with foot-tall bright yellow flower stems favored by hummingbirds and butterflies alike. I often joke that our local hummingbirds are illiterate, unable to read the books which say the birds only feed on red flowers. I see hummingbirds feed on many flowers, from both herbaceous and woody species, with Salvia species near the top of the favorites list. 

Bog Sage
S. uliginosa
One of the the consistent aspects of growing either annual or perennial sages is they need some pruning and fertilizing care to keep them in good shape. Left to their own devices, these plants will grow into fairly rank and unkempt weeds. Routine trimming of stems and removal of old flower stems will keep them looking good.

Many of the landscape types will re-seed, or can be propagated by stem cuttings. These plants look best in clusters or grown as specimens, especially if used as a wildlife attractant.    

The larger perennial species and varieties can make quite a statement in the landscape, with plant sizes from petite to giant, and flowers colors from pink through azure blue and even burgundy. I visited San Marcos Growers in Santa Barbara years ago, marveling at the array of Salvia types that can grow in balmy southern California. I was stunned by the variety of flowers and plant sizes available, as well as the frenzy of hummingbirds staging their own gang wars, fighting over the best flowers for nectar. The effect of the flowers and plant textures was memorable, and I hope to add several species here at Pinecrest Gardens.   

Scarlet Sage
S. coccinea,
 in 2
color forms

With moderate care, some advance knowledge of the plant's ultimate size, and some thought on how to integrate the plant into a landscape, the Sage group can be a valuable and rewarding addition to a landscape. The only real restriction is sunlight: most of the species are sun-lovers, and intolerant of shade.

Craig Morell
Pinecrest Gardens

S. greggii

Forsythia Sage
S. madrensis

August 7, 2012

A Great Alternative to Turf Grass

With an increasing trend toward water conservation throughout the country ( aided by a record-setting nationwide drought), we should take a new look at our need for turf grass in its current application. In so many landscaped areas, I see turf grass in places it should not, cannot, or  never will grow. Researchers come up with new turf varieties that are drought tolerant, new types of grass that are shade tolerant, and new products to tend to the burgeoning array of turf varieties. Yet again and again, I see turf in places where something else would do the job better. The question I have is: why do we HAVE to have grass over every bare area or open spot ?
There are egregiously expensive commercial turf cutting machines that cost as much as a small house, turf fertilizers that contain some VERY interesting ingredients with unusual names, and a truly impressive array of turf chemicals to treat insects, pathogens and soil compaction. If you look at all these factors, a curious person might ask why we have such a passion for something that needs so much care, water, and other resources. 
I know there are great alternatives, and one in particular fits a lot of needs perfectly. Decades ago, university researchers found a neat little groundcover called Perennial Peanut that grows really well in sunny areas with good drainage. Some varieties are especially suited to growing in nearly arid conditions, perfectly suited to parking lots and roadway applications, whereas some varieties grow better in light shade. All varieties of perennial peanut spread quickly, and can be planted as plugs or small potted plants, planted about 1 foot apart. The resulting mat of vegetation grows tightly enough to crowd out weeds, the cheery yellow flowers are a nice bonus to the green foliage, and the plants are tough enough to withstand light foot traffic. To my knowledge, there are few reports of diseases or pests which affect Perennial Peanut.This plant requires very little maintenance, and can even be mowed with a turf mower to maintain a desired height.        

Marketed under the name of 'Eco-Turf', this plant has been around a long time, introduced into Florida in the late 1950s, but fairly widespread since the 1980s. There are several varieties, but usually the variety sold in your particular area is suitable for your conditions. Perennial Peanut can grow in a dozen different US states, so there are options available for gardeners in the Gulf as well as the Eastern seaboard. The plant can be obtained in both sod and plug form, establishing quickly with less water and care than for grass sod. Perennial Peanut also requires far less fertilizer or water than grass sod. Where it is practical, consider planting some of this versatile and different material. I have never heard a complaint of it becoming invasive, or overgrowing the bounds in which it was planted. With the Green Movement in full swing, why not try something that grows with less effort, sweat or money while keeping your garden green....?  

Craig Morell
Pinecrest Gardens