Choosing a Tree for Your Landscape

Choosing a Tree for Your Landscape

American fringetree Chionanthus virginicus), a native deciduous small tree with delicate blooms in spring. Photo credit: Mary Salinas, UF/IFAS Extension.

January and February are ideal months for adding a tree or two to your landscape in the Florida panhandle. In the cooler weather, the ground stays moist for a longer time, which helps prevent drought stress and the drying out of the rootball. Also, the winds are generally milder, and the tree will have a chance to get established and anchored in before the wilder winds of summer roll in.

Before investing time and money in a tree, take a few minutes and be sure that the species you choose is right for your particular landscape.

Here are some things to consider:

  • Whether the area can accommodate the ultimate size of the tree, both height and width, and not grow into overhead wires, streetlights, or your house.
  • Are there any underground utilities or septic? A call to 811 can check on where your utilities are.
  • The hardiness zone for the tree. Be aware that zone 8 or 9 in the western United States is a different climate with respect to moisture than the same zone 8 or 9 in Florida.
  • Whether the tree can thrive in your soil – sandy, loam or clay, loose or compacted, high and dry, or wet and low.
  • The amount of sun it requires.
  • Whether you want native species that provide food and habitat for native birds and animals.
  • Salt-tolerance if located on the coast.
  • Wind tolerance, especially if located on the coast. Many fast-growing trees are brittle and susceptible to breakage.
  • Whether you prefer an evergreen or deciduous tree. Evergreen trees, like hollies, provide a natural screen all year while some deciduous trees, like maple and bald cypress, provide fall color.
  • Is the tree messy, dropping large seed pods, fruit, or leaves?
  • The color and shape of leaves and flowers and other ornamental qualities.
  • Whether the tree species has known disease or pest issues.

Florida red anise (Illicium floridanum), a small tree/large shrub for shady locations. Photo credit: Mary Salinas UF/IFAS Extension.

Once you choose what species of tree you will add to your landscape, here’s information on Selecting Quality Trees from the Nursery.

Optimum tree health and vigor also depends on the correct methods of Planting and Establishing Trees.

And this site has even more comprehensive information on trees and shrubs: University of Florida/IFAS Landscape Plants.

Tough Plants for Tough Weather

Tough Plants for Tough Weather

Stoke’s aster ‘Mel’s Blue’ 20 days after Hurricane Sally’s landfall. Notice how soil was washed away from root ball, all the leaves emerged post-hurricane. Photo credit: Mary Salinas, UF/IFAS Extension.

Hurricanes can wreak havoc in your landscape, but they can also reveal what plants are the toughest and most resilient. It’s a great learning opportunity.

A few weeks ago, Hurricane Sally came along and brought about 10 feet of surge and waves across my landscape and completely covered everything except the tallest trees for about 18 hours. (Fortunately, our house is on stilts and we did not have intrusion into our main living areas.)

As expected, the trees, including Dahoon Holly and Sweetbay Magnolia, took a beating but stayed intact. With their dense fibrous root system, most of the clumping native grasses also stayed put.

Perennial milkweed 3 weeks post-hurricane. New topsoil and compost now covers the rootball. Photo credit: Mary Salinas, UF/IFAS Extension.

The most surprising plant species that survived were about a dozen Stoke’s aster and 3 perennial milkweed.  4-5 inches of soil all around them was washed away, most of the roots were exposed, and the leaves were stripped or dead. The other perennials that had lived nearby were all washed away. To my surprise, within about 10 days after the storm, these two plant species started poking up new stems and leaves.

Here’s a list of some of the plants either in my yard or in the neighborhood that survived Hurricane Sally’s storm surge and may be suitable to add to your coastal landscape:

  • Dahoon holly, Ilex cassine
  • Muhly grass, Muhlenbergia capillaris
  • Dwarf Fakahatchee grass, Tripsacum floridanum
  • Perennial milkweed, Asclepias perennis
  • Stoke’s aster, Stokesia laevis, specifically the cultivars ‘Mel’s Blue’ and ‘Divinity’
  • Bottlebrush, Callistemon citrinus
  • Gardenia, Gardenia jasminoides
  • Bougainvillea, Bougainvillea spp.
  • Flax Lily, Dianella tasmanica
  • Crapemyrtle, Lagerstroemia spp.
  • Cabbage palm, Sabal palmetto
  • Canary Island date palm, Phoenix canariensis
  • Sweetbay magnolia, Magnolia virginiana
  • Augustinegrass, Stenotaphrum secundatum
  • And, unfortunately, the rhizomes of the invasive torpedograss also survived.

For more information on salt tolerant and hurricane resistant plants, see:

UF/IFAS Gardening Solutions: Coastal Landscapes

UF/IFAS Gardening Solutions: Salt-tolerant Lawngrasses

UF/IFAS Gardening Solutions: Trees That Can Withstand Hurricanes

 

Aphids & Milkweed

Aphids & Milkweed

Perennial milkweed, Asclepias perennis, with oleander aphids; notice the brown aphid mummies that have been parasitized. Photo credit: Mary Salinas UF/IFAS Extension.

Milkweeds are appreciated for their beauty, but often we cultivate it for the benefit of the monarch butterflies who lay their eggs only on this plant genus. Avid butterfly gardeners want the monarch caterpillars to eat up the milkweed and become beautiful butterflies. Often instead, thousands of aphids show up and compete for space on the plants. These bright yellow aphids are known as oleander aphids.

Just how do aphids build up their populations so quickly? It seems that one day you have a small number on a few plants and then a few days later, thousands are all over your milkweed. Oleander aphids have a few advantages for quickly building their populations:

  • All oleander aphids are female and do not need to mate to produce their young
  • Aphids give birth to live young who immediately start feeding on the plant
  • Aphids start reproducing when they are 4 to 10 days old and keep reproducing during their one-month life span
  • When populations get heavy or the plant starts to decline, winged individuals are produced to migrate to new areas and plants.

Parasitic wasp and aphid mummies. Photo credit: University of California.

 

What can or should you do to control this pest?

One option is to do nothing and let the natural enemies come in and do their job. One of the best is a very tiny wasp that you will likely never see. This parasitoid lays its eggs only inside aphids. The wasp larva feeds on the inside of the aphid and turns it into a round brown ‘mummy’ and then emerges when mature by making a round hole in the top of the aphid. Look closely with a hand lens at some of those brown aphids on your milkweed and you can see this amazing process. Another common predator I see in my own garden is the larvae of the hover fly or syrphid fly. You will have to look hard to see it, but it is usually there.  Assassin bugs and lady beetles also commonly feed on aphids. The larvae of lady beetles look nothing like the adults but also are voracious predators of aphids – check out what they look like.

Lady beetle larva feeding on aphid on tobacco. Photo credit:
Lenny Wells University of Georgia Bugwood.org.

If you think your situation requires some sort of intervention to control the aphids, first check carefully for monarch eggs and caterpillars, keeping in mind that some may be very small. Remove them, shoo away any beneficial insects, and spray the plant completely with an insecticidal soap product. Recipes that call for dish detergents may harm the waxy coating on the leaves and should be avoided. The solution must contact the insect to kill it. Always follow the label instructions. Soap will also kill the natural enemies if they are contacted. One exception is the developing wasp in the aphid mummies – fortunately, they are protected inside as the soap does not penetrate. Oils derived from plants or petroleum can serve the same purpose as the insecticidal soap.

Syrphid fly larva and oleander aphids. Photo credit: Lyle Buss, University of Florida.

You also can squish the aphids with your fingers and then rinse them off the plant. If you only rinse them off, the little pests can often just crawl back onto the plant.

There are systemic insecticides, like neonicotinoids, that are taken up by plant roots and kill aphids when they start feeding on the plants. However, those products also kill monarch caterpillars munching on the plant and harm adult butterflies, bees, and other pollinators feeding on the nectar. So those products are not an option. Always read the product label as many pesticides are prohibited by law from being applied to blooming plants as pollinators can be harmed.

In the end, consider tolerating some aphids and avoid insecticide use in landscape.

Happy butterfly gardening!

Meet Mary Salinas

Meet Mary Salinas

Mary is the Residential Horticulture Agent and Master Gardener Volunteer Coordinator for UF/IFAS Extension in Santa Rosa County.  She earned a B.S. and M.S. in environmental horticulture at the University of Florida. She and her volunteers provide research-based solutions for residents with their lawns, landscapes, and gardens. Mary also oversees the educational programs, horticulture, butterflies, and volunteers at the Panhandle Butterfly House & Nature Center that has just relocated to Milton and should reopen in 2021.

Mary Salinas at the US Botanic Garden in Washington, D.C. Photo credit: Allison Ngom.

Ever since she can remember, Mary has loved plants and nurturing them. She learned how from her mother and grandmother growing up with good rich soils in Michigan.  A relocation to Tampa in 1991 meant learning a whole new way to garden – new plants, new soils, and new timetables. Nearly eight years ago she moved north to Santa Rosa County to take her current position and, again, had to tweak her garden skills.

Between she and her husband they have 6 children and 4 grandchildren and are hoping for more grandchildren real soon. Family and faith are a priority. At home, Mary loves to try new crops and varieties in her vegetable garden and is passionate about growing perennials, especially native milkweeds, and watching new generations of monarch butterflies take flight. And she is fascinated with huge container gardens. Gardening is not the only activity in her life; Mary loves to kayak, cruise in the pontoon boat, hike, and volunteer as a guardian ad litem for children in foster care.

Plants Can Do Unexpected Things

Plants Can Do Unexpected Things

Fasciation of Rudbeckia hirta ‘Toto Rustic’. Photo credit: Mary Salinas, UF IFAS Extension.

You never know what surprises are looming in your flower gardens.

This Rudbeckia in the photo to the left sported one bloom that was so different from all the others. The disk or central portion of the inflorescence was elongated and curved back on itself and created a contorted, crazy looking bloom. And then there was a yellow squash in my garden that had a leaf growing down the length of the squash. What caused these things to happen?

Fasciation in yellow summer squash. Photo credit: Mary Salinas, UF IFAS Extension.

This is a mutation, often genetic, but also could be caused by outside influences such as pathogens, injuries, or chemicals. Plant hormones may also play a role in this phenomenon. This mutation expresses itself as a malformation or cresting at the tip or growing point of the plant, also known as the meristem. We call this fasciation and it begins when the cells at a growing point of a plant start dividing in an uneven or asymmetrical fashion instead of the normal symmetrical pattern.

A gerbera daisy affected by fasciation. Photo credit: Mary Salinas, UF IFAS Extension.

There are some plants we embrace for their fasciation. A common one is cockscomb celosia that is prized for its showy crested inflorescence. Cacti and succulents more commonly exhibit fasciation and we can see it in some of the crested cacti.

Take a close look at what is happening in your garden and landscape. Plant biology is fascinating!

Cockscomb Celosia inflorescence. Photo credit: Lee Terilla 2008, some rights reserved.