Wednesday, July 31, 2013

Prevent Brown Patch or Pythium Blight with Crabapple LandscapExperts’ Lawn Management Tips

Cool-season grasses like Fescue stay green during the winter. These lawns are stressed by hot metro-Atlanta summers. To that, add in the heavy downpours and wet weather we have been experiencing in this record-breaking year, and some turfgrass can succumb to diseases, such as the  descriptively named Brown Patch (caused by Rhizoctonia solani) and Pythium blight a.k.a. oil spot (caused by Pythium spp.) as the result of hot, wet weather.
Pythium Blight on Fescue
Brown Patch on Fescue

Best practices by Crabapple LandscapExperts help to reduce the incidence of Brown Patch and Pythium Blight on cool-season Fescue lawns.  

  • Avoid nitrogen applications when the disease is active 
  • Increase the height of cut
  • Mow frequently
  • Don't mow when wet <-- a challenge this year! 
  • Use a sharp blade in the lawn mower to avoid raggedy torn edges, an entry point for diseases
  • Increase the air circulation 
  • Minimize the amount of shade by limbing-up shade trees and pruning shrubs to reduce the shade 
  • Irrigate turf early in the day to speed up drying off. Fungus spores can only germinate in standing water 
  • Improve the drainage of the turf, easiest to do during installation, add permatill or coarse sand 
  • Reduce thatch through core aeration 
  • Rake leaves or debris off of the grass 
  • Apply lime if soil pH is less than 6.5 
  • N-P-K fertilizers: use low to moderate amounts of nitrogen, moderate amounts of phosphorous and moderate to high amounts of potash  
  • Fungicides are available to control the disease. Consult the current GeorgiaPest Management Handbook -- commercial or homeowners version 

For additional help with turf diseases and their remedies, phone your Crabapple Rep at 770-740-9739. Our program for commercial properties includes preventative and systemic fungicides. 

Wednesday, July 24, 2013

Companion Planting, a Win-Win Proposition

Photo credit blog
 Crabapple LandscapExperts are asked, “What is companion planting?”

Companion planting is the belief that certain plants can benefit target crop plants if planted together in close proximity. Companion planting is a form of “polyculture” and involves planting different types of plants next to each other for mutual benefit. The opposite is a “monoculture” such as a corn field or putting green on the golf course, where only one type of plant is grown in the space.
 Companion plants:

Use garden space efficiently, with two or more plants growing in the same spot 
For example, 
tomatoes with marigolds
Prevent pest problems by repelling pests
catnip reduces the number of flea beetles on cabbage and collards
Lure pests away from crops because they prefer the sacrificial plants 
 peppers and ragweed
 Help each other grow
 vining pole beans growing up tall corn plants

 Attract beneficial insects such as predators and pollinators more efficiently than crop plants
 zinnia nectar and a cauliflower crop
 Provide shade for crop plants 
short lettuce with taller cleome or nicotiana

By combining plants the gardener draws on the strengths of each. For example, French Marigolds are often planted with tomatoes, since both enjoy sun and hot weather.  Research has shown that chemicals exuded by the roots of marigolds eliminates certain types of root-knot nematodes that otherwise damage the tomato roots, causing swellings on the roots or causing the roots to form like short clubs, which makes the uptake of water and nutrients impossible.

French marigolds
Although a row of short French marigolds planted beneath tomatoes provides a memorable photo, Crabapple LandscapExperts advise the gardener to plant a solid bed of marigolds first, before planting with tomatoes, in order to drastically reduce the number of soil-borne root-knot nematodes.  
Aother example is planting carrots and onions in order to benefit both crops. The smell of the Allium covers the smell of the carrot foliage, and insects have more difficulty finding them and mostly eliminates carrot fly damage (larvea invade carrot roots).  In exchange, the carrot performs the same service to the onions, acting to confuse the onion fly.
Often a row of roses is under planted with chives, garlic chives or garlic because they are said to repel Japanese beetles and other rose pests. Whenever planting Tulip bulbs, be sure to plant a clove of garlic in the planting hole to repel larger pests (mammals) like chipmunks or pine voles, thereby ensuring that the colorful tulips will come up and flower next spring.  
Chives Blossom 
Strong-smelling herbs and plants that are said to repel pests or otherwise benefit other plants include chives, nasturtiums, mints, pennyroyal, garlic, tansy and French marigolds.  Despite numerous testimonials, however, the University of Georgia Extension says further research is needed to verify many claims of the effects of companion plantings.

Digging Deeper

Wednesday, July 17, 2013

Assessing Wind Damage to Trees

On Friday severe wind and storms came racing through parts of metro-Atlanta, damaging property, power lines and landscape trees and plants. Meterologists called the storm a "microburst" meaning that strong winds hit the ground and traveled straight, unlike the spinning winds of a tornado. 

If this happened to a property you manage, give CrabappleLandscapExperts a call and let us explain the steps that our professional landscape maintenance service performs after such a wind event.

The LandscapExperts Make Observations
We approach damaged trees with caution, particularly if there are large dangling branches or power lines caught in the trees. Call the LandscapExperts if in doubt (770-740-9739)

Crabapple Assesses the Damage

Uprooted multi-trunked tree
Q Was the tree uprooted and physically tipped-over, or has there been damage to the structural roots in the root zone due to the wind load?
A High winds pushing against the branches can uproot a tree, particularly those with heavy crowns, shallow roots, or those standing in waterlogged ground after a rainy summer. 

Q Is 50% or more of the crown (branches, twigs, leaves) intact?
A the 50% rule is a good rule of thumb as to whether or not the tree has enough leaves left to photosynthesize and survive, although other factors such as the time of year and the opportunity for watering also play a big role.

Q Other than the storm damage, is the tree basically healthy and vigorous?
A Of course a young, healthy tree stands the best chance of recovery. Past tree abuse, stressed conditions, poor maintenance, disease and pest problems can pre-weaken a tree, making it harder for it to recover. 

Q Has the leader been lost? (the main upward growing branch) Can a whip near the top of the tree be successfully trained to be the new leader? 
A To prevent a mis-shapen or deformed tree, a strong upright growth leader should remain viable and a twin-leader situation be avoided.

Limb ripped from trunk
Q Are major limbs broken?
A The larger the limbs lost, the harder it will be for the tree to recover. Trees canopies tend to grow to fill the space, and if limbs on one side are ripped off a young tree may look 2-dimensional for awhile. Evaluate if there are small branches or twigs already placed and "aimed" at the empty spot that can grow to fill the void.

Q Will the remaining branches be able to form a balanced, new branch structure?
 A Look for small twigs and branches aimed in the correct direction to elongate and fill in gaps in the crown, or make a 2-dimensional tree a nice, rounded 3-dimensional one after the passage of a few years. 

Old wound, healed over,
elliptical shape
Q How big are the wounds, and is the bark ripped?
A The larger the wound is in relation to the size of the limb, the less likely it will be to heal. Large wounds can be the point of entry for fungal and bacterial pathogens. Crabapple carefully ripped bark to an elliptical shape that will seal over with new bark within a couple of years. Rubber straps or bands can be used until the greenwood (cambium layer) knits together after storm damage (similar to grafting techniques).  

Crabapple LandscapeExperts can provide answers to these questions and evaluate the damage and the chances for repair and success for you.

Digging Deeper
A devastating storm hit London in October, 1987 blowing over millions of trees and lots of articles followed-up 25 years later. For example, Kew Gardens in London some drastic measures were used to upright and replant a few venerable trees while many were lost and the park replanted. 

Wednesday, July 10, 2013

Rainy Day Mushrooms

Edible Shitake mushrooms grow on oak log
Did you know? Not all fungi is bad. Although many plant diseases are caused by pathogenic fungi, some soil fungi help to break down dead plant material into rich, black humus, making the nutrients available to plants. Often their white threadlike strands (hyphae = singular / mycelium = plural) can be found throughout the soil.  Other friendly fungi (mycorrhiza) attach to the roots of green plants and help them absorb more water and extra minerals and nutrients, in effect extending their root system. Humans eat edible mushrooms like portabellos and white button 'shrooms as a tasty and nutritious vegetable. Beneficial Penicillin is a form of fungus, while wine and cheese are created by the action of the yeast fungus.

Most fungi thrive in warm, moist conditions. After 30+ days of rain in metro-Atlanta, there are plenty of mushrooms popping up across the city in mulch, in shady areas, in lawns and even in paths and flower beds. Mushroom experts can tell which of these are edible, and which are deadly poisonous. Mushrooms are actually the "fruiting bodies" of various fungi and they eventually mature and send off dust-like mushroom spores as the way mushrooms reproduce (not seeds, but the same idea).

While mushrooms or toadstools appearing the lawn may be annoying, they usually do not harm turf. There is nothing to be applied to the soil to prevent them from emerging. Crabapple LandscapExperts just mow or rake them off and remove them as they appear.

Fairy Ring of Mushrooms in Lawn
A "fairy ring" of mushrooms in the lawn is created when spores land in on the grass and start to grow. They use up the nutrients at that spot and start to grow outward from the initial spot in a uniform way, searching for more nutrients and causing a ring. As they die, they return the nitrogen in their mushroom bodies to the soil, creating a ring of bright green grass just inside the ring of actual 'shrooms.

Digging Deeper
To learn more about mushrooms, try the Mushroom Club of Georgia, a knowledgeable group that meets for programs about mushrooms and to go on hikes to find and gather them. "Like" the Mushroom Club of Georgia on Facebook, here. 

Amazing post about little-known fungi capabilities here: The Power of Mushrooms to Save the Planet

Wednesday, July 3, 2013

Fast-acting, Foliar Feeding

Royal Standard Hosta
in bloom

Crabapple LandscapExperts point out that plants are able to absorb nutrients directly through their leaf surfaces; the epidermis and stomata. Foliar feeding is the term used for applying water-soluble liquid fertilizer directly to the leaves of a plant.

Although Foliar Feeding will never take the place of soil application of fertilizers, and in some cases, claims for the effectiveness of foliar feeding have been exaggerated, it is especially useful in cases of deficient soils or in extremes of soil pH that limit nutrient availability and uptake. Foliar feeding is also ideal for supplying the plants with trace elements, the essential nutrients that are required in very tiny amounts, as well as for a temporary or targeted spot-fix for the fast uptake of nutrients. This quick-action is the most widely agreed upon benefit, that nutrients can more quickly reach all parts of the plant than by root feeding. Noted Michigan State Horticulturist H.B. Tukey performed a landmark experiment in the 1950s using radioisotopes to trace the movement of nutrients through plants.

A classic use for foliar feeding is the application of Iron Chelate to pinpoint iron-deficieny in plants.

Fruiting plants such as tomatoes and blueberries can benefit from foliar feeding during the flowering stage, feeding when the flowers first appear and again when tiny fruits begin to form, as well as a few more times during the growing season.

  • Often, organic fertilizers such as compost tea, diluted worm compost or seaweed tea are used. Try making Compost Tea by soaking a shovel-ful of rich, homemade compost in a couple of gallons of water, then straining out the compost (and returning it to the compost pile), and using the "tea" as a foliar spray.
  • Diluted concentrations of chemical fertilizers like Rapid-gro or Miracle-Gro(R) fertilizers can also be sprayed directly on the leaves to add micronutrients and for a boost in fertility. .   
Woody ornamentals benefit
from foliar feeding

Digging Deeper
Extension Horticulturist and UW Associate Prof Dr. Linda Chalker-Scott points out that while foliar feeding does not take the place of soil applications, it is useful in several ways.