Crabgrass and Summer Annual Weed Control

Crabgrass and Summer Annual Weed Control

Spring is approaching and the main thing on my mind is controlling annual weeds. The most effective way to control crabgrass and other summer annual weeds is with a pre-emergent herbicide. Pre-emergent herbicides should be applied prior to weed seed germination. They don’t prevent germination, but they do prevent emergence of shoots and roots by forming a barrier on the soil surface.

Crabgrass plant growing in centipedegrass lawn
Crabgrass growing in centipedegrass lawn. Photo credit: UF/IFAS Extension

Summer annuals such as crabgrass and chamberbitter begin to germinate when soil temperatures warm in the spring. Preemergence herbicides should be applied when daytime temperatures reach 65oF to 70oF for 4 or 5 consecutive days to form a barrier to help prevent these weeds from emerging. This is about the same time azaleas and dogwoods begin to bloom. Goosegrass is the exception for this temperature rule. For good goosegrass control, preemergence herbicides should be applied 3 to 4 weeks after the suggested daytime temperature application date.

It is important to note that you should only use preemergence herbicides on lawns that have been established for at least a year. These herbicides are prone to injure newly planted lawns. In addition, many preemergence herbicides may interfere with lawn grass seed germination, so make sure to refrain from reseeding for at least six after application.

Commonly available preemergence herbicides contain the active ingredients oryzalin, benefin, pendimethalin, DCPA and bensulide. However, there are a wide variety of products on the market. For more information on weed management please read the UF/IFAS publication “Weed Management Guide for Florida Lawns”.

Twig Pruners and Girdlers

Twig Pruners and Girdlers

Not all fall color is a good thing. This statement is especially true when it comes to twig pruners and twig girdlers. These two species of longhorned beetles can certainly disappoint your grand expectations of a beautiful array of fall color. Both species cause the tips of twigs to fall to the ground in late summer, sometimes leaving your trees in an undesirable form.

Twig Pruners

The twig pruner (Elaphidionoides villosus or Anelaphus villosus) is a small longhorned beetle that attacks numerous species of hardwoods. It is usually classified as a secondary pest of declining trees and shrubs. Female twig pruners lay their eggs in late spring at the leaf axils. When the eggs hatch, the grubs bore into twigs and continue to bore as they mature. The larvae then chew concentric rings just underneath the bark. The infested twigs and branches eventually drop to the ground with the larvae inside. The larvae pupate inside the fallen twig throughout the winter.

An adult twig pruner
An adult twig pruner. Photo Credit: University of Georgia

Twig Girdlers

The twig girdler (Oncideres cingulata) is a small longhorned beetle that invades many species of hardwoods. Female twig girdlers lay their eggs in late summer in small twigs (about 3/8 inch diameter) that are covered with a thin layer of bark. The female chews a concentric ring around the outside of the twig, causing the end of the twig to die. The female chews a small notch in the dead twig and lays her eggs. After the eggs hatch, the larvae feed on the dead twigs and develop into adults before chewing their way out. The adults fly away to new host trees.

An adult twig girdler
An adult twig girdler. Photo Credit: Lacy L. Hyche, Auburn University

Management and Control

It’s important to plant the right plant in the right place. Healthy trees and shrubs are the best defense against insect pests. Twig pruners and twig girdlers live in dying or dead twigs and branches. If you have trees that have suffered damage from these pests you will notice an abundance of fallen twig ends around the base of your trees. Rake and remove fallen twigs from around the trees and destroy or dispose them. This will help reduce pruner and girdler numbers in subsequent years.

Screen Trees for Privacy and Noise Reduction

Screen Trees for Privacy and Noise Reduction

Sometimes we just need a little privacy. This is especially true if you live on a busy road or just have annoying neighbors. There are a few things to consider when selecting a screen tree: 1) full-grown size; 2) speed of growth; and 3) aesthetics. With these three factors in consideration, let’s review some screen options for different situations.

Pineapple guava
Pineapple Guava (Acca sellowiana) hedge. Photo Credit: Daniel Leonard, University of Florida/IFAS Extension – Calhoun County

Pineapple Guava (Acca sellowiana)

At one time this shrub was hard to find, but it is slowly becoming more available. Pineapple guava is native to South America, but it adapts well to the Florida Panhandle. This plant can reach 10 to 15 feet in height with an equal spread and has a moderate rate of growth, so it’s a great choice when you just need a small screen. Pineapple guava is moderately salt-tolerant and does well in coastal landscapes. As a bonus, the flowers and fruit are edible. It’s hard to find a more aesthetically pleasing large shrub. Pineapple guava is evergreen with leathery green leaves that have grey undersides. This plant can be grown as a large shrub or pruned to be a small tree.

'Emily Bruner' Holly
A large ‘Emily Bruner’ holly at the Santa Rosa County Extension Office. Photo Credit: Matt Lollar, University of Florida/IFAS Extension – Santa Rosa County

‘Emily Bruner’ Holly (Ilex x ‘Emily Bruner’)

‘Emily Bruner’ holly is a cross between the Chinese holly (Ilex cornuta) and the lusterleaf holly (Ilex latifolia). This evergreen shrub has glossy green leaves. It has a pyramidal growth habit and is listed as reaching 15 to 20 feet tall by 5 to 8 feet wide, however the specimen at the Santa Rosa County Extension Office is about twice that size. ‘Emily Bruner’ holly prefers moist, well-drained soil. This holly has dense, prickly leaves so it does well keeping people out of your yard in addition to buffering sound. The flowers have a sweet scent and are a favorite of honey bees.

Dahoon Holly
Dahoon holly foliage and berries. Photo Credit: University of Florida/IFAS

Dahoon Holly (Ilex cassine)

Dahoon holly is native to North America, is tolerant of wet, shady sites (but can also handle full sun), and displays some salt tolerance. This evergreen, small tree is somewhat shrubby. It can grow to be 25 to 30 feet in height with an 8 to 12 foot spread. Dahoon holly has nice light green leaves that are smooth, not prickly like ‘Emily Bruner’ holly. It has a moderate growth rate.

cultivar magnolia
Bracken’s Brown Beauty as an accent tree in a lawn area. Photo Credit: Beth Bolles, University of Florida/IFAS Extension – Escambia County

Southern Magnolia (Magnolia grandiflora)

It’s hard to beat a majestic southern magnolia in the landscape. Why not utilize it as a screen tree? Now, not all southern magnolias are made equal. There are a few cultivars that do well as screens as well as on their own. ‘Bracken’s Brown Beauty’, ‘Claudia Wannamaker’, and ‘D.D. Blanchard’ are three that come to mind and are readily available in the trade. Southern magnolias can reach up to 80 feet tall and 20 to 40 feet wide depending on cultivar and growing conditions. Not only do these three cultivars have beautiful dark green, leathery leaves, their leaves also have brown undersides. These versatile trees can tolerate are variety of soil conditions and they are very wind resistant. And as another bonus, they have beautiful, fragrant flowers.

Eastern Redcedar
Middle-aged Juniperus virginiana ‘Burkii’: Burk Eastern Redcedar. Photo Credit: Ed Gilman, University of Florida/IFAS

Eastern redcedar (Juniperus virginiana)

If your looking for softer texture in your landscape, then you can’t go wrong with a cedar tree. Unbeknownst to its name, eastern redcedar can be found growing all over the United States. This evergreen conifer prefers well-drained sites in full sun. It can grow 30 to 40 feet in height by 10 to 20 feet wide. Eastern redcedars have good salt tolerance. These trees produce beautiful, blue-green foliage. One key to growing this tree successfully is to give it space. Plant trees 12 to 24 feet apart. If using as a screen, you may consider staggering this tree to give it the space it needs.

There are lots of good options when selecting trees for a screen. It’s important you select plants that fit the site. The University of Florida has an excellent plant selection tool found at the Florida Trees for Urban and Suburban Sites webpage.

Mums – Not Just a Fall Decoration

Mums – Not Just a Fall Decoration

Chrysanthemums in different colors
Chrysanthemums in different colors. NC State Extension

Fall hasn’t even started and the garden centers are already filled with mums. Somehow I made that sound like a bad thing. Chrysanthemums look great in containers at the front door and planted in the garden too. They also last pretty long as cut flowers. And they’re not just a fall decoration, mums are a great addition to the garden for years.

Mums have deep-green, lobed foliage with soft gray undersides. They are available in a number of colors, from dark red and orange to lavender and pink to white. Mums bloom when nights start to get longer in late summer and fall. Some species and varieties can be used as low-growing groundcovers and others can grow to 5 feet tall. All are herbaceous perennials that can continue to bloom for years.

Mums prefer full sun to partial shade. They like slightly acidic, well-drained soil that is rich in organic matter. Use slow-release fertilizer to ensure an even flow of nutrients throughout the season. Keep plants looking attractive and healthy and full of new blooms by dead heading. You may also choose to choose to cut of side buds on main shoots to create larger flowers.

Mums can be propagated by either division or cuttings. It is important to either divide and re-pot potted plants or transfer potted plants to larger containers to keep plants from becoming root bound. Chrysanthemums are relatively pest free, but spider mites can become a problem in hot, dry weather. Make sure plants receive water regularly in hot, dry weather.

Everglades Tomato Doesn’t Disappoint

Everglades Tomato Doesn’t Disappoint

For me, tomatoes are the most difficult (and expensive) vegetable to grow. I even try to discourage people from growing tomatoes in Florida. Tomatoes are susceptible to damage from a plethora of diseases and insect pests AND they require a lot of maintenance and fertilizer. However, I now have a tomato variety I can recommend – The Everglades Tomato.

The Everglades tomato (Solanum pimpinellifolium) is a different species than the traditional tomato (Solanum lycopersicum). Other names for this tomato are the wild tomato or currant tomato. The plant produces an abundance of small tomatoes (about 1/2 inch diameter) with thin skin. Unlike most tomatoes, Everglades tomatoes keep producing throughout the heat of summer. They are even tolerant of brackish water and salt winds.

Everglades tomatoes should be cared for like any other indeterminate (vining type) tomato. Like most gardeners, I like to plant tomatoes a little deeper (two inches or so) than they were planted in the tray/pot. This allows for more adventitious roots to develop from the buried portions of the stems. I also like to trellis these plants with tall stakes and twine or some other support to improve air circulation. However, I have read that Everglades tomatoes grow just fine rambling on the ground. Make sure to give them a little more space than other tomatoes regardless if you stake them or not. Fertilize and irrigate just the same as you would for other tomatoes.

harvested Everglades tomatoes
A bountiful harvest of Everglades tomatoes. Photo Credit: Connie Gladding, Master Gardener Volunteer, University of Florida/IFAS Extension – Clay County

Of course, just like any plant, Everglades tomatoes aren’t perfect. Their small size makes harvesting a little more labor intensive and their thin skin is easily torn. But I’m able to look past these faults because of their excellent flavor. I’ve also noticed Everglades tomatoes are not immune to caterpillar/moth pests. Fortunately the caterpillars only seem to feed on the leaves, because the tomatoes are so small.

Whether you’re a chef or just want a sweet snack, you should give Everglades tomatoes a try. Just search the internet for seed sources or ask a friend for a cutting.