June 23, 2011

Water Quality DOES Make a Difference....

private conservatory at garden of Dr. Jeff Block, South Miami
anchored by a robust Angiopteris evecta

For years I grew plants that were "fussy" and otherwise described by a range of colorful adjectives. Some of them included Cochliostema, Medinilla, certain Licuala species, Gardenias, Vireya Rhododendrons, and a long list of orchids. When I moved from West Palm Beach back to Miami, I found that the plants fared even worse in many cases, even thought he climate was proclaimed to be better. I thought the problems with the plants were due to the wetter weather of Miami . Perhaps the problem was the wrong potting mix, so I tried dozens of combinations, looking for yet another miracle of soilless medium technology, or a fix-all fertilizer. None of the "cure-all" methods worked. Over many years, I marveled at some of the Miami growers who could grow these temperamental plants so well. I was puzzled  about the reasons for their success until I ran into a few growers in the area where I now live, who explained that it was the good quality water in this area.

Cochliostema odoratissima

In every grower's life, there are epiphanies, and for many reasons. Mine was that the answer to growing many of these unusual plants was better water quality, and it was one of the oldest answers in the world. One of the last clinching proofs of this was my first visit to a small garden near my home, designed and administered most expertly by Dr. Jeff Block, a retired anesthesiologist and highly awarded plant collector.  Many of his plants are of better quality and larger size than any I've seen, and one of the main reasons is his commitment to providing the plants with excellent water, mainly  reverse-osmosis ( RO ) water. His irrigation well water is excellent, too, allowing many of his in-ground plants to grow to grand stature. In many venues, be they palms, tree ferns, orchids, bromeliads or begonias, his plants are champion size and growing robustly. The same results can be achieved by using rainwater.  

Tacca integrifolia
The White Bat Plant

The main point to be learned is that so many of the interesting plants we love come from rainforest or tropical areas where there is abundant clean rainfall. Using high-pH or calcium laden water will slow down or cause harm to many plants. Many botanical gardens have installed RO units for their exotic plant collections with very notable results. One of the best examples is the legendary Atlanta Botanical Garden, with a stunning example of the high-altitude ecosystem of Venezuelan Tepuis. Growing these plants requires a rare combination of ultra-clean water, continuously cool moving air, and a great knowledge of the plants. Ron Determan is the expert grower for the Fuqua Conservatory at Garden, and his results are worth the trip. As many veteran growers of exotic plants will report, rainwater or distilled water is the "real" thing, and RO water comes pretty close. There are a few items to consider with using rainwater, though.

A stunning Vireya Rhododendron hybrid

Should you collect rainwater off a galvanized roof, the collected water will have a lot of zinc in it, bad for some plants. Rainwater from a roof loaded with plant debris will also have insects and plant parts in it, and possibly fungi from decaying vegetation. In heavily urbanized areas, smog and pollutants may dissolve in rain, and be a hazard to the plants. Still, rainwater is better than tap or municipal water. Many university extension agents are recommending the use of rainbarrels, a practice I heartily recommend,  especially if you have a greenhouse or rare plant collection. I modified the practice by using a small electric sump pump, attached to a garden hose, and dropped into the barrel. Plug in the pump and you get full pressure rainwater through a garden hose for your plants, a practice I found much more useful than toting the water one gallon at a time.

I recommend using rainwater or RO water for your most delicate and sensitive plants, especially in containers. This will help a lot to avoid the buildup of soluble salts from fertilizer, as well as avoid any calcium buildup. Keeping in mind that rainwater or RO water contains neither of these, most any plant will respond to the "improved"' water with marked improvements in new growth.

A perfect bed of Begonia imperialis,
with an accent plant of a Vriesia fosteriana hybrid
One thing to note in Dr. Block's collection is the great colors in the foliage and flowers. I have seen these results before, but in the wet areas of coastal Hawaii, where there is a lot of rainfall, along with moving, humid air. Dr. Block has perfectly tuned the climate in his shadehouses by using under-bench misting, along with circulation fans to create the climate his plants need. The staghorn ferns , bromeliads, orchids and other epiphytes thrive with the RO mist and dilute fertilizer they receive so consistently. The water quality issue is easy to prove in such a garden, where the difference between success and poor growth is the water quality. 
The technology is easy enough to install an RO unit in your home, especially if you wish to grow plants which need the cleanest water they can get, such as carnivorous plants, many rainforest epiphytes, plants in vertical gardens or "green wall" projects, and a host of others. Try a few barrels of rainwater on recalcitrant plants and see what happens, and let the plants show you what you've been missing.  

Medinilla magnifica

Craig Morell
Pinecrest Gardens

All photos courtesy of Dr. Jeff Block
Block Botanical garden
South Miami, Florida

June 21, 2011

Blazing Sun Bromeliads

Alcantarea imperialis, flanked by Aechmea blanchettiana

One of the more popular questions I get is what kinds of bromeliads can take full sunlight. It is an interesting question and a hard one to answer, since "full sun" can mean either direct sunlight for a short period, or all-day sun without shade. The two conditions are quite different ! Many of the hard-leaved bromeliads can take a few hours of direct morning sunlight and will benefit from it. The same plants placed into all-day sunlight will likely sun-burn to crisp, literally.  I believe it would be safe to say that most bromeliads enjoy bright filtered light, as seen under an oak or poinciana or a cluster of pine trees. This "shifting shade" is excellent; it has all the sun energy the plants need without all the scorching heat. Some of the hardest-leaved species actually need direct sunlight for several hours to get the best leaf color.

Alcantarea imperialis rubra

The same tolerance for sunlight can be said of most gardeners, too. We enjoy a bright spot in the garden, but very few of us enjoy working in the hot afternoon sun. There are some bromeliads species that will grow and thrive in the most intense sunlight we have to offer, and as such these plants are also fairly thrifty in their water demands. Let's look at some of these plants, many of which are rock or tree-dwellers. The plants might be a little hard to find, but there are several bromeliad societies in Florida and California, and their plant sales are excellent.  

Neoregelia johannis
a sun-loving giant to 4 feet across

Vriesia hieroglyphica
 There are numerous species in the genera Aechmea, Alcantarea, Billbergia, Quesnelia, and Vriesia which enjoy strong light to all-day sunlight. Most of these plants need water in the center of the plant more frequently than they need water at their roots, but in most cases the plants qualify as xeriphytes. They like very occasional, low-nitrogen fertilizer, and a well-drained potting medium that allows plenty of air to circulate amongst the roots. The plants do need watering every week, but are hardly demanding of it.

Neoregelia carcharodon

Neoregelia MacWilliamsii,  one of the most prolific
and sturdy of landscape bromeliads

There are myriad choices for bromeliads for strong light- morning sunlight, and even all-day sunlight. Don't limit yourself to the plants available at bog-box garden centers, spend a bit of time and go to a bromeliad society sale, or to a botanical garden sale. The members and staff are willing to assist in getting the right plants for your garden, and can lend some excellent advice about keeping the plants in top shape. As with so many landscape plants, use your options of local knowledge and the vast array of plants available to you.

Craig Morell
Pinecrest Gardens


June 13, 2011

The Gorgeous Licuala Group

Licuala ramsayi
Lundkvist Garden, Hawaii

I admit that I am a plantaholic, with no reservations or excuses. I have devoted most of my life to the art and craft and occasional science of growing plants. Every plantsman I know has favorite genera or plants. In my case, I have favorite plant families . Fortunately I get to work in a botanical garden where I can grow a wide range of plants within families, and sometimes show off the differences in a genus. One of my favorite genera is Licuala, with which I've had an affinity for decades. There is something elegantly simple about the leaves in the genus. Perhaps my fascination is due to my early reading of the massive Exotica plant book when I was a teenager, seeing the pictures of the plant from far-off Thailand or Java. I always thought of them as tender, fussy plants for collector's conditions, but this is not always the case.  At Pinecrest Gardens, we have several species of Licuala, mostly the larger species such as lauterbachii,  grandis, ramsayi, peltata 'sumawongii' and spinosa. I stay away from the real collector's items like 'mapu' which need more protected conditions and better water quality than we have here. The genus lends itself well to tropical and sub-tropical gardens, where the species can handle a wide range of growing conditions and water qualities. On Miami Beach at La Gorce Country Club, there are several species of Licuala growing on the golf course, proving that with ample water and fertilizer, some species can grow under "commercial" growing conditions. In Singapore, I saw hundreds of grandis growing as boulevard plantings on Scotts Avenue, and even at shopping malls in Miami, I see spinosa and grandis as massed plantings. The Ruffled Fan Palm is still seen at palm sales, and is still a desirable landscape plant, provided it gets some protection from cold and windy conditions.  The palms will show large brown patches of damage, which can take several years to grow out of.

Licuala grandis
The Ruffled Fan Palm

The availability of Licuala species has risen such that many species are available at reasonable prices, although the demand has risen as well, so only small plants are easily found, with larger plants still fetching some decently large prices. One of the most surprising species has been the recently-rare species peltata 'Sumawongii'. What was surprising was its durability to cold and windy weather for the last several years in Miami. We had several in the ground and they tolerated 35 degrees for several nights. Our other species were heavily damaged, but the Sumwong plants had no damage at all. As such, we just finished planting 18 more large Sumawong palms about 6 feet tall, making one of the largest groups of this species I know of in the country. It grows about the same speed as grandis, but the leaves get twice the size, are somewhat flatter, and are held farther apart.  

Licuala peltata 'Sumawongii
with George Bailey
There are numerous species in the genus, and some are mature at just a few feet tall. One of the real jewels in the genus is mattanensis 'Mapu', and even in Miami this is a conservatory plant. Under the right conditions, it looks surreal, with its freckled foliage and dappled-sun patterns. Dr. Jeff Block in South Miami has a great specimen of this species, but he has a conservatory fitted for such conditions, including reverse-osmosis water, acid soil, and total protection from wind. 
Licuala mattanensis 'mapu'

the elegant and petite
Licuala orbicularis
    Many species in this genus are easy enough to grow in landscapes in South Florida. Keep in mind, though, that most of these species come from very stable forest or rainforest conditions, meaning that they need an even supply of water, moist soil, and plenty of mulch to keep the roots supplied with organic material. Some of the species will do well in very sunny conditions, but most like shade in the afternoon. They will propagate from seed quite readily, but be aware they are really slow growing. This explains their relatively high cost ! Most species need to be in pots until they are at least 3 or 4 years old, and would appreciate a lot of organic soil amendments in the planting hole.

Licuala spinosa,
enjoys strong light and has some tolerance for cold weather
This palm genus is one of nearly 100 which will grow in our area. This is another great example of the diversity we have available to us, and another reason why I rail against the frequency of local landscape designs that look like every other part of Florida, rife with Queen Palms and pink Ixoras. We can grow plants in this area unavailable and ungrow-able anywhere else in the country. Let's use the options available to us !!
Craig Morell
Pinecrest Gardens

June 10, 2011

Mango Mania- Coming Soon to a Neighborhood Near You

'Haden' Mango, one the most prolific commercial varieties

Over the last few weeks, several counties in South Florida have seen record fruit-set on their mango trees. This happens when we've had the weather we experienced last year and the year before: periods of cold weather followed by months of dry sunny weather from January to April, perfect for the abundant production of  flowers. This weather combination allows for good insect pollination and the lack of rain allows the flowers to turn into fruit without rotting off in rainstorms. 

'Carrie' Mango, one of the sweetest tasting
mango varieties

The dilemma is that when mango trees set a lot of fruit, they often set a LOT of fruit, sometimes more than can be eaten or sold. ( What a dilemma, I say). I sometimes get a question from newcomers to the area about how many mango trees can be put on a half-acre lot. My answer is "3". They respond that they REALLY love mangoes, and would like to buy 10 or 12 trees for their lot. My return question is "can you really eat 1000 pounds of fruit in one season....? " There is often dead silence on the other end of the phone.

Back in August 2010, I wrote a blog about Dwarf Mango trees for small spaces. Many residents in this part of the state can handle a large tree, and some may even want a large growing mango. For them, there are hundreds of varieties, and there is a wide range of atstes for the fruit as well.

'Keitt' Mango, one of the largest mango fruit varieties-
easily weighing 3 pounds or more per fruit
a commercial variety, excellent taste, fiberless and sweet

There are so many excellent mango varieties available for this area that the hardest choice to make is which varieties to plant. There are several mango tasting festivals in the South Florida area during Summer, and the trees are readily available for sale. There are varieties to suit your taste, garden size, and to a smaller degree, fruiting season. Mango trees will set fruit from may to September, occasionally October. Some of the commercial varieties ( used in large scale mango production) can set several hundred pounds of fruit per tree. The so-called "dooryard" or "condo" mango varieties will still set 50-200 pounds of fruit per tree on a smaller-stature  tree.

For best fruit set and the healthiest tree, mango trees need all-day sunlight, some protection from hard frost, well drained soil, and low-analysis fruit tree fertilizer 3 times per year at most. Many local experts suggest a "tough love" style of culture for the trees, meaning that the tree does not need to be over-cultivated. Give the trees the intense sun they require, great soil drainage, and an occasional fertilizing, then let Mother Nature do her thing.

Craig Morell
Pinecrest Gardens

June 6, 2011

The Calendar Says It Is Spring, But It Is 93 Degrees.....and Climbing

drip lines can be connected to a hose
and are really efficient

The western states are MUCH drier than Florida
and use more creative watering methods

Every year, we experience a phenomenon I call "The Transition"; the period between the pleasant weather of Spring, and the brutal sun and heat of Summer. Unfortunately, this transition period involves long days of brilliant, cloudless skies, little or no rain, and fairly strong dry winds. These forces combine to make plants ( and gardeners) really unhappy. The results are painfully evident, with great patches of dry grass, wilting and defoliating trees, wilted everything else, and a renewed questioning in the wisdom of having tropical gardens. 

Take heart, fellow gardeners, the rains are coming. This happens every year, but the length of these dry spells seems to get longer and longer each year. I can't speak to the idea of global climate change, but I could certainly speak to the ideas of local climate change, and a disappearing water table. What can we do as a residence, business, and community to bring relief to our plants, without breaking any ethical or legal conservation laws ? 

My answer is that we can do several things to make our plants happier in the dry times, using techniques I have brought forth before in previous blogs. Let's revisit some of these ideas, starting with intelligent watering practices. Using large amounts of irrigation water for a few minutes each day is counter-productive, and nets you shallow root systems that need watering daily to survive. Using less water over a longer time ( e.g drip or soaker lines on the soil under mulch) will give plants the water they need with no runoff and almost no wasted water.

drip emitter set on a durable sub-
surface drip tube line

Using larger amounts of mulch or compost is a great way to save water and get better looking, more drought-resistant plants. Use more mulch, not less, and use it more often, not less often. Keep mulch away from the tree trunks or stems, and strive to apply 4-6" of mulch in the entire area under the tree or shrub canopy, out to the canopy edge and even beyond. Some of the better looking low-maintenance gardens I've seen locally had no grass, a thick bed of mulch and pine straw over the whole garden, and the plants looked fabulous. Grass is an enormous consumer of water and fertilizer, to say nothing of the time and expense of keeping it cut and weed-free. 

If you simply must have turf grass, water it intelligently, deeply, and weekly. So many people water their lawns every day ( unnecessary), feed the grass monthly ( unnecessary), and spend egregious amounts of money on weedkillers and pesticides ( unnecessary). Moreover, there are turf maintenance companies which trumpet the need for high-nitrogen fertilizers, guaranteeing that their product will green up the grass almost overnight. The tree and palm and shrub roots that grow throughout the property certainly don't need this extra nitrogen, and can even be harmed by it. In Florida, an N:P:K ratio of 3-1-3 is ideal, e.g. a 12-4-12 fertilizer, or a Palm Special type of fertilizer. If you really want an extra punch in the fertilizer product, choose extra potassium, the last ingredient in the mixture, such as 12-4-15. This extra potassium level gets you stronger roots, greener color, and solid tree / palm roots, without speeding up plant growth. 

Last and not least, look at where your irrigation is applying water--you might be watering a sidewalk, road, driveway, or patio deck. These areas won't absorb water, and will evaporate water fast, wasting it into the air, not into the ground. Water your property early in the morning, before 9 a.m. to slow down evaporation into the atmosphere. The old dogma of watering at mid-day is wasteful and unproductive. The best effects come when irrigation is done near dawn. 

We can all conserve a little water without any impact on our lives, saving water at every step. Together the numbers add up to impressive levels: if every household and business in Florida watered one day less than we currently do, billions of gallons of water would be saved every year.