Cut Back Tropical Milkweed

Cut Back Tropical Milkweed

Tropical milkweed, Asclepias curassavica, has become a commonly grown monarch host plant in many gardens. It grows very well in our climate and survives into Fall and Winter during many years. This long life of Tropical milkweed is not necessarily a good trait for the monarch butterfly. In the Fall, monarchs are in migration mode and need to move out of our area to overwinter in warmer climates. Live host plants that are found during migration may interrupt the process. An additional problem is that Tropical milkweed may be host to a disease caused by a parasite that can impact the health of Monarch butterflies. The best tip to help our migrating Monarch butterflies, is to cut back your Tropical milkweed to the ground each Fall or better yet, grow native milkweeds that usually die back on their own.

North Florida Goldenrod

North Florida Goldenrod

Autumn Blooms

The days are getting shorter, the sun setting earlier each day, and the temperatures are beginning to dip.  All the signs are there, we’ve reached autumn which means it’s time for many roadside wildflowers to begin their bloom cycle.  Surely, you’ve seen them as you drive down the road, small colorful patches in the ditch or as almost blinding yellows across vast fields. The vibrant yellow in this latter example is that of goldenrod (Solidago spp.).  A name attributed to many plants in Asteraceae better known as the Daisy family, they serve to feed pollinators when other plants begin to fade.  Two of the most common in the panhandle are seaside goldenrod (Solidago sempervirens) and Canada goldenrod (Solidago canadensis).

Coastal Goldenrod

Seaside goldenrod will be most prevalent in the coastal counties along the panhandle. It thrives on beach dunes in tidal marshes and disturbed coastal areas. Tolerance to saline soils and sea spray allow growth in these environments.  A clumping perennial, it grows to 6.6 feet clumping with a 1.6 foot spread.  The flowers of this plant bloom in autumn on a spiked inflorescence as tubular disk florets. They are pollinated by several types of insects and birds. This plant was used as far back as the Roman times to treat several medical conditions.

Photo: Joshua Criss

Inland Goldenrod

Canada goldenrod is found in Florida almost exclusively in the panhandle with a few pockets as holdouts in the peninsula.  Not as common along the coast, this plant prefers to take hold in ditches and open meadows.  At 1-7 feet tall with it spreads via underground stems known as rhizomes.  Rhizomatous plants such as these are traditionally difficult to control and may become weedy in some situations. Yellow ray style flowers present in clusters at the end of stems on drooping panicles. Pollen form this plant is often blamed for fall allergies, but does not tend to travel far on the wind making this an unlikely source. As with the seaside goldenrod, this plant was used traditionally as a medicine in ancient times. 

Photo: Joshua Criss

Summing it up

Goldenrod along with many autumn blooming wild flowers may be something you’ve put very little thought into.  They are proven winners in terms of late season pollinator support. Often overlooked in the home landscape, plants like goldenrod may bring a new twist to your home gardens.  They require little water and fertilizer and grow well in our area.  For more information on Florida wildflowers, see these Ask IFAS documents, or contact your local extension agent for additional information on this and any topic regarding your gardens and more.

False Foxglove:  A Unique Fall Wildflower

False Foxglove: A Unique Fall Wildflower

False Foxglove in a Calhoun County natural area. Photo courtesy of Daniel Leonard.

Fall is the absolute best season for wildflower watching in the Panhandle!  When mid-September rolls around and the long days of summer finally shorten, giving way to drier air and cooler nights, northwest Florida experiences a wildflower color explosion.  From the brilliant yellow of Swamp Sunflower and Goldenrod, to the soothing blue of Mistflower, and the white-on-gold of Spanish Needles, there is no shortage of sights to see from now until frost.  But, in my opinion, the star of the fall show is the currently flowering False Foxglove (Agalinus spp.).

Named for the appearance of their brilliant pink flowers, which bear a resemblance to the northern favorite Foxglove (Digitalis spp.), “False Foxglove” is actually the common name of several closely related species of parasitic plants in the genus Agalinus that are difficult to distinguish by all but the keenest of botanists.  Regardless of which species you may see, False Foxglove is an unusual and important Florida native plant.  Emerging from seed each spring in the Panhandle, plants grow quickly through the summer to a mature height of 3-5’.  During this time, False Foxglove is about as inconspicuous a plant as grows.  Consisting of a wispy thin woody stem with very small, narrow leaves, plants remain hidden in the flatwoods and sand hill landscapes that they inhabit.  However, when those aforementioned shorter September days arrive, False Foxglove explodes into flower sporting sprays of dozens of light purple to pink tubular-shaped flowers that remain until frost ends the season.

False Foxglove flowering in a Calhoun County natural area. Photo courtesy of Daniel Leonard.

In addition to being unmatched in flower, False Foxglove also plays several important ecological roles in Florida’s natural areas.  First, False Foxglove’s relatively large, tubular-shaped flowers are the preferred nectar sources for the larger-sized native solitary and bumble bees present in the Panhandle, though all manner of generalist bees and butterflies will also visit for a quick sip.  Second, False Foxglove is the primary host plant for the unique Common Buckeye butterfly.  One of the most easily recognizable butterflies due to the large “eye” spots on their wings, Common Buckeye larvae (caterpillars), feed on False Foxglove foliage during the summer before emerging as adults and adding to the fall spectacle.  Finally, False Foxglove is an important indicator of a healthy native ecosystem.  As a parasitic plant, False Foxglove obtains nutrients and energy by photosynthesis AND by using specialized roots to tap into the roots of nearby suitable hosts (native grasses and other plants).  As both False Foxglove and its parasitic host plants prefer to grow in the sunny, fire-exposed pine flatwoods and sand ridges that characterized pre-settlement Florida, you can be fairly confident that if you see a natural area with an abundance of False Foxglove in flower, that spot is in good ecological shape!

The Florida Panhandle is nearly unmatched in its fall wildflower diversity and False Foxglove plays a critical part in the show.  From its stunning flowers to its important ecological roles, one would be hard-pressed to find a more unique native wildflower!  For more information about False Foxglove and other Florida native wildflowers, contact your local UF/IFAS County Extension office.

 

Chaste Tree

Chaste Tree

Photos by Sheila Dunning

The showy chaste tree makes an attractive specimen as the centerpiece of your landscape bed or in a large container on the deck.  Much more of them are being seen since the Florida Department of Transportation has recognized the tree as a desirable median planting.  Easy-to-grow, drought resistant, and attractive to butterflies and bees, Vitex agnus-castus is a multi-stemmed small tree with fragrant, upwardly-pointing lavender blooms and gray-green foliage.  The chaste tree’s palmately divided leaves resemble those of the marijuana (Cannabis sativa) plant; its flowers can be mistaken for butterfly bush (Buddleia sp.); and the dry, darkened drupes can be used for seasoning, similar to black pepper, making it a conversation piece for those unfamiliar with the tree.

Vitex , with its sage-scented leaves that were once believed to have a sedative effect, has the common name “Chastetree” since Athenian women used the leaves in their beds to keep themselves chaste during the feasts of Ceres, a Roman festival held on April 12.  In modern times, the tree is more often planted where beekeepers visit in order to promote excellent honey production or simply included in the landscape for the enjoyment of its showy, summer display of violet panicles.

Chaste tree is native to woodlands and dry areas of southern Europe and western Asia.  It will thrive in almost any soil that has good drainage, prefers full sun or light shade, and can even tolerate moderate salt air.  Vitex is a sprawling plant that grows 10-20 feet high and wide, that looks best unpruned.  If pruning is desired to control the size, it should be done in the winter, since it is a deciduous tree and the blooms form on new wood.  The chaste tree can take care of itself, but can be pushed to faster growth with light applications of fertilizer in spring and early summer and by mulching around the plant.  There are no pests of major concern associated with this species, but, root rot can cause decline in soils that are kept too moist.

Landscape  Q & A

Landscape Q & A

On August 12, 2021, our panel answered questions on a wide variety of landscape topics. Maybe you are asking the same questions, so read on!

Ideas on choosing plants

What are some perennials that can be planted this late in the summer but will still bloom through the cooler months into fall?

Duranta erecta ‘Sapphire Showers’ or ‘Gold Mound’, firespike, Senna bicapsularis, shrimp plant, lion’s ear

Where can native plants be obtained?

Dune sunflower, Helianthus debilis. Photo credit: Mary Salinas UF/IFAS Extension.

Gardening Solutions: Florida Native Plants  – see link to FANN: https://gardeningsolutions.ifas.ufl.edu/plants/ornamentals/native-plants.html

What are some evergreen groundcover options for our area?

Mondo grass, Japanese plum yew, shore juniper, ajuga, ferns such as autumn fern.

What are some ideas for partial morning sun butterfly attracting tall flowers to plant now?

Milkweed, salt and pepper plant, swamp sunflower, dune sunflower, ironweed, porterweed, and salt bush.

I’m interested in moving away from a monoculture lawn. What are some suggestions for alternatives?

Perennial peanut, powderpuff mimosa, and frogfruit.

We are new to Florida and have questions about everything in our landscape.

Florida-Friendly-Landscaping TM Program and FFL Web Apps: https://ffl.ifas.ufl.edu/

https://ffl.ifas.ufl.edu/resources/apps/

UF IFAS Gardening Solutions: https://gardeningsolutions.ifas.ufl.edu/

What are some of the top trends in landscaping today?

Houseplants, edible gardens, native plants, food forests, attracting wildlife, container gardening, and zoysiagrass lawns

Edibles

Artwork broccoli is a variety that produces small heads. Photo credit: Mary Salinas UF/IFAS Extension.

What vegetables are suitable for fall/winter gardening?

Cool Season Vegetables: https://gardeningsolutions.ifas.ufl.edu/plants/edibles/vegetables/cool-season-vegetables.html

North Florida Gardening Calendar: https://edis.ifas.ufl.edu/publication/EP451%20%20%20

Florida Vegetable Gardening Guide: https://edis.ifas.ufl.edu/publication/vh021

How can I add herbs to my landscape?

Herbs in the Florida Garden: https://gardeningsolutions.ifas.ufl.edu/plants/edibles/vegetables/herbs.html

My figs are green and hard. When do they ripen?

Why Won’t My Figs Ripen: https://www.lsuagcenter.com/profiles/rbogren/articles/page1597952870939

What is best soil for raised bed vegetable gardens?

Gardening in Raised Beds: https://edis.ifas.ufl.edu/publication/EP472

And there are always questions about weeds

How can I eradicate cogongrass?

Chamber bitter is a troublesome warm season weed in our region. Photo credit: Brantlee Spakes Richter, University of Florida, Bugwood.org

Cogongrass: https://edis.ifas.ufl.edu/publication/WG202

Is it okay to use cardboard for weed control?

The Cardboard Controversy: https://gardenprofessors.com/the-cardboard-controversy/

What is the best way to control weeds in grass and landscape beds?

Weed Management Guide for Florida Lawns: https://edis.ifas.ufl.edu/publication/EP141

Improving Weed Control in Landscape Planting Beds: https://edis.ifas.ufl.edu/pdf/EP/EP52300.pdf

Landscape practices

Can ground water be brackish and stunt plants?

Reclaimed Water Use in the Landscape: https://edis.ifas.ufl.edu/publication/ss545

How can I prevent erosion from rainwater runoff? 

Stormwater Runoff Control – NRCS: https://www.nrcs.usda.gov/wps/portal/nrcs/detail/national/water/?cid=nrcs144p2_027171

Rain Gardens: https://gardeningsolutions.ifas.ufl.edu/design/types-of-gardens/rain-gardens.html

And https://gardeningsolutions.ifas.ufl.edu/pdf/articles/rain-garden-manual-hillsborough.pdf

What is the best time of the year to propagate flowering trees in zone 8B?

Landscape Plant Propagation Information Page – UF/IFAS Env. Hort: https://hort.ifas.ufl.edu/database/lppi/

Which type of mulch works best on slopes greater than 3 percent?

Landscape Mulches: How Quickly do they Settle?: https://edis.ifas.ufl.edu/publication/FR052

When should bulbs be fertilized?

Bulbs and More – UI Extension: https://web.extension.illinois.edu/bulbs/planting.cfm

Should I cut the spent blooms of agapanthus?

Agapanthus, extending the bloom time: https://gardeningsolutions.ifas.ufl.edu/plants/ornamentals/agapanthus.html

http://blogs.ifas.ufl.edu/wakullaco/2020/10/07/extending-bloom-time/

Plant questions

Monarch caterpillar munching on our native sandhill milkweed, Asclepias humistrata. Photo credit: Mary Salinas, UF IFAS Extension.

I planted native milkweed and have many monarch caterpillars. Should I protect them or leave them in nature?

It’s best to leave them in place. Featured Creatures: Monarch Butterfly: https://edis.ifas.ufl.edu/pdf/IN/IN780/IN780-Dxyup8sjiv.pdf

How does Vinca (periwinkle) do in direct sun? Will it make it through one of our panhandle summers? Can I plant in late August?

Periwinkles  and  No more fail with Cora series: https://gardeningsolutions.ifas.ufl.edu/plants/ornamentals/periwinkles.html#:~:text=Plant%20your%20periwinkles%20where%20they,rot%20if%20irrigated%20too%20frequently.

Insect and disease pests

What to do if you get termites in your raised bed?

The Facts About Termites and Mulch: https://edis.ifas.ufl.edu/publication/IN651

How to combat fungus?

Guidelines for ID and Management of Plant Disease Problems: https://edis.ifas.ufl.edu/publication/mg442

Are there preventative measures to prevent diseases when the humidity is very high and it is hot?

Fungi in Your Landscape by Maxine Hunter: http://blogs.ifas.ufl.edu/marionco/2020/01/16/fungi-in-your-landscape/

 

If you missed an episode, check out our playlist on YouTube https://www.youtube.com/watch?v=bp0HfdEkIQw&list=PLhgoAzWbtRXImdFE8Jdt0jsAOd-XldNCd

 

Florida Wildflowers: Brown-eyed Susan

Florida Wildflowers: Brown-eyed Susan

Brown-eyed Susan makes a nice addition to a pollinator garden. This one is visited by a scoliid wasp, a parasitoid of soil-inhabiting scarab beetle larvae. Photo credit: Mary Salinas, UF/IFAS Extension.

Black-eyed Susan, Rudbeckia hirta, has been a very popular garden perennial for generations. Fewer gardeners have experience with, or even heard of its’ close relative, brown-eyed Susan, Rudbeckia triloba. So, what is the difference between them?

  • Brown-eyed Susan has more numerous flowers and generally flowers for a longer period in spring, summer, and fall.
  • Black-eyed Susan has bigger flowers and bigger leaves.
  • Both species are perennial, but the brown-eyed Susan tends to die out sooner after a few years. The good news is that both readily spread through seed to replace older plants.

    Brown-eyed Susan. Photo credit: Mary Salinas, UF/IFAS Extension.

Brown-eyed Susan is native to the eastern and central United States and, although native to Florida, it has only been vouchered in the wild in 5 counties in Florida. Gardeners can find seed and plants readily online and at a few native plant nurseries. It is best to try to source wildflower seed from plants grown in the same region. Brown-eyed Susan seed from plants grown in Nebraska or Michigan may not be as well adapted to the Florida environment as locally grown seed.

If you want to add this pollinator attracting perennial to your garden, choose a spot that is sunny or partly sunny. Although it prefers moist soil, brown eyed Susan adapts to most soil types and is drought tolerant after establishment.