by Daniel J. Leonard | Jun 22, 2016
Gardeners in Northwest Florida were blessed this spring with conditions conducive to great gardening, mild weather and plenty of rain. However, with those pleasant conditions has come an unusually high occurrence of Fireblight. Cases of Fireblight have been brought into our office almost daily this spring/early summer!
Mature ‘Bradford’ Pear infected with Fireblight
Fireblight is a difficult to control, rapidly-spreading disease caused by a bacterium (Erwinia amylovora) that affects many fruit trees, especially apple and pear but is also seen on quince, crabapple, hawthorn, loquat and photinia. Fireblight is generally noticed in late winter and early spring during periods of frequent rainfall as the plant begins to bloom and leaf out. The bacterium enters the plant through the opening flowers causing them to blacken and die. The disease then makes its way down the infected stem, destroying newly developing twigs along the way. Most homeowners notice the problem at this point in the progression; the new shoots have died, turned black and hold on the plant, giving it the tell-tale “burned” look. Homeowners also generally notice sunken lesions, or cankers, that form on the infected stems.
So, with a problem as unpredictable and destructive as Fireblight, what can one do to prevent it or combat its spread? There is no one method that can prevent or cure a Fireblight infection but there are several precautions homeowners can make to mitigate its effects.
- Plant resistant species and/or resistant cultivars of susceptible species, such as pear and apple. Under conditions like we’ve had this year, no pear or apple is immune but these cultivars have some proven resistance:
- Edible Pear: ‘Keiffer’, ‘Moonglow’, ‘Orient’
- Apple: ‘Anna’, ‘Dorsett Golden’
- Ornamental Pear: ‘Bradford’, ‘Cleveland Select’
- Remove infected and dead wood when the tree is dormant. Make a clean cut at least 12” below the last sign of infected wood and dispose of it. It is always a good practice to sanitize your pruners between cuts on a diseased tree. Also, there is little evidence to suggest that pruning out diseased wood on actively growing plants has much effect on further disease spread as long as conditions are still suitable for Fireblight formation.
- If you have noticed Fireblight on your trees in the previous year, it is good practice to make a preventative spray of a copper fungicide prior to the plant breaking dormancy.
- During bloom, streptomycin may be applied every three or four days for the duration of the bloom cycle to prevent infection. Consult the label for required days between spraying and consumption.
Fireblight is bad news in a fruit orchard but homeowners can take heart in the fact that the condition is not always fatal, especially if the preventative measures outlined above (proper cultural practices, proper pesticide use, and planting of resistant cultivars) are taken!
by Daniel J. Leonard | Apr 27, 2016
People are, by nature, skeptical. Humans are and have always been questioners of the world around them and that’s a good thing! For instance, when one reads a sensational article on Facebook or watches an infomercial selling a too-good-to-be-true product he/she is immediately dubious of the veracity of the claim. Given this innate sense, why do consumers take plant tags displayed on retail plants and the information listed there as infallible fact when in reality they are often full of hyperbole and misleading?
I do not mean to insinuate that nurseries and landscape professionals are intentionally leading consumers astray. They are not. However, there is much incorrect information disseminated to consumers by the green industry on plant fact sheets. Take my titular example, ‘Little Gem’ magnolia is widely advertised and sold as a “dwarf” magnolia, only growing 15’-25’ tall. If given proper care, it will grow to that height…in seven to ten years. Given enough time, ‘Little Gem’ has will grow in excess of forty feet. People plant this cultivar under the eaves of single story houses on a regular basis! I promise that cute little magnolia you were told would grow 15’ tall will look rather silly when it is four times the height of your house. Take another example, how many times have you seen or heard of ‘Acoma’ crapemyrtle being sold as a “semi-dwarf” cultivar that grows to 10’ in height for use in a tight spot of the landscape in lieu of the much larger ‘Natchez’? It will fill that tight spot and fill it rather quickly. ‘Acoma’ can easily reach 20’ in height and width at maturity, engulfing its intended area.
Typical plant tag. Notice the “Average Size” section. This is where consumers should use discretion.
So why does this happen? Why are plant tags so often mistaken? There are two primary reasons that correct mature sizes are not given. First, in the competitive world of plant breeding and introduction where there can be hundreds or thousands of cultivars of a single species, it is of utmost importance to introduce plants as quickly. Quick introduction is necessary because others are probably working to find similar traits; therefore, if one notices that a plant possesses a drastically different flower, flowering pattern, leaf shape, leaf size, or growth habit, the plant is often rushed to market. This leaves little time for complete trials of the plant to see what it would look like at maturity.
Secondly, most well-adapted or native trees/shrubs have relatively long life spans. A crapemyrtle or magnolia can easily grow and thrive in a landscape for thirty years or more before reaching maximum size. Nurseries simply do not have time to evaluate plants that long. Many nurseries, due to vagaries of economic cycles and length of career spans, don’t even exist for thirty years much less trial a single plant for that length of time!
In conclusion, nurseries are not likely to change their plant tag practices, but there are a couple of checks consumers can use to make sure they buy an appropriate plant for the scale of their site. First, it is a good rule of thumb to double the advertised plant height to arrive at a better idea of the plant’s mature size. Second, drive through established neighborhoods and observe what certain plants look like in a mature landscape. This will give one an idea of what the plant is capable of. The third and best option is to consult your local County Extension Office. They will be able to offer research-based information to help you make the right decision in your plant choices. Keep this in mind the next time you are thinking of buying the latest, greatest plant at your local nursery!
Happy Gardening!
by Daniel J. Leonard | Mar 23, 2016
One of the major issues homeowners face in their landscapes is selecting a tree that in maturity will be in scale with the rest of their garden and home. While we have several actual trees that fit the bill, I would like to focus today on thinking outside the box by selecting a larger growing shrub that we can “limb up” into a small tree!
Loropetalum in its tree form
Today’s plant is Loropetalum chinense, also known as Chinese Fringe Flower, a beautiful import related to our native Witchazels (Hammemelis spp.). Some species of Loropetalum can have green foliage and white flowers, but it is generally found in its coveted maroon-foliaged form, which is the subject of this piece. Most cultivars of Loropetalum (with the exception of a few newer ‘dwarf’ cultivars) are large (to 20’ tall and about half as wide) evergreen shrubs that prefer partial shade to full sun. In the early spring, it bursts with wavy, fringe-like red, pink, or white flowers!
In order to “tree-form” the plant, one should gradually begin removing lower lateral branches, crossing or rubbing branches, and any potentially diseased branches, leaving 5-7 main trunks. Eventually, most common cultivars of Loropetalum can easily be pruned to have 4’-5’ of exposed trunk!
Unfortunately, Loropetalum has been both overused and misused as a tightly sheared foundation plant in every landscape imaginable, from gas stations to Aunt Gertie’s rental house. As such, it has gotten a bad reputation as a monster that has to be constantly sheared to keep it in line. This reputation is completely unwarranted if using the shrub as it was meant to be used, as a large specimen shrub or a graceful small-tree! Yet another example of how using the right plant in the right place can change the public’s entire perception of it! Try tree-forming a Loropetalum today and enjoy it for years to come! Happy Gardening!
