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A Tale of Two Hoses

A Tale of Two Hoses

A common site in the garden – multiple hoses pieced together. Be aware of galvanic corrosion! Credit: Tyler Jones, UF/IFAS.

It was the best of times, it was the worst of times. It was a nice day in the garden, but when you go to disconnect the hose, it is somehow stuck to the spigot, connector, or other hose. You go and get the pliers, but the hose just doesn’t budge. If this has happened to you, then you now know of the chemical reaction that can occur between aluminum and brass hose fittings. Hopefully, this is just two hoses stuck together, and you can cut them off and replace them with new ends. If the hose is connected to the spigot and won’t budge, you may want to contact a plumber before you create a bigger problem.

While knowing the name of this chemical reaction, galvanic corrosion, doesn’t help you while you curse these hose fittings, it is yet another scientific discovery in the garden. Galvanic corrosion occurs when two dissimilar metals are in electrical contact with each other in the presence of an electrolyte. The metals must be dissimilar in their electrochemical voltage. I know, you just want to disconnect hoses, not learn physics, but this stuff is interesting! Basically, aluminum is pretty reactive, especially when joined up with brass, bronze, copper, and even stainless steel. In the case of our hoses, the water acts as an electrolyte thanks to the calcium present in our delicious and abundant limestone aquifer groundwater. You put all these together and, bazinga, you have the aluminum hose end corroded into your brass hose end so strongly that no pliers will ever unlock them.

This won’t work out well for too long! Aluminum hose end on a brass spigot will lead to galvanic corrosion. Credit: Mark Tancig, UF/IFAS.

So, what do you do to prevent this? The easiest way to prevent galvanic corrosion from ruining your nice day in the garden is to only purchase products with the same material as your spigots. Brass spigots, hose bibs, and hose ends have been the industry standard, while aluminum hose endings seem to be more of a recent occurrence. Aluminum is cheaper, so you can understand why the hose companies would be interested in switching. If you already have two different materials, first check and see if you can get them disconnected. If not, start purchasing new hoses that match the spigot and/or connector. If you can get them disconnected, one method to prevent galvanic corrosion is to just disconnect them regularly to avoid them fusing. Not sure if you’ll remember? You can also use a plastic connector between the hoses to make sure the two metals don’t touch each other or switch out the aluminum hose ends with replacement brass or plastic ends, found at most hardware stores.

A quick fix is to place a plastic connector between the dissimilar metals. Credit: Mark Tancig, UF/IFAS.

Now that you’ve learned about galvanic corrosion, it’s time to get back to gardening. Good luck with those hoses! If you have other gardening questions, please contact your local extension office.

Cold Protection for North Florida

Cold Protection for North Florida

Another North Florida winter is here! With that comes a new plants from leafy greens to snapdragons.  It also means the inevitable freeze is on the way. It is prudent for all gardeners to review what needs to be done to protect your non-freeze hardy plants.

Hardiness Zones

Before we get into what actions you may need to take, let’s examine plant hardiness zones. These are geographic areas created by the US Department of Agriculture defined by their average extreme minimal temperature. In the Panhandle these are zones 8b through 9b. In winter we will likely see low temps between 15 – 30 degrees depending on your zone. Sourcing plants appropriate for your zone can mitigate quite a bit of cold damage in your landscape. If you like plants susceptible to the cold, you can interplant them to add a little protection.

Microclimates

Find and utilize your yard’s microclimates. Areas under larger trees are likely to remain warmer in the winter. This is also true behind a windbreak, or near a structure with high sun exposure. Look around your yard and plant any cold sensitive plants in these areas.

Planted area with many microclimates

This area is likely to have multiple microclimates. UF/IFAS Photo

 

Full Season Plant Care

Cold protection begins with warm season plant care.  Pay close attention to the irrigation and fertilization needs of your landscape plants. Apply these properly to ensure stress free plants moving into the colder months as these will perform better as the mercury begins to drop.

Imminent Freeze Actions

Ok, now that everything is planned, we know our microclimates, and we’ve cared for our landscape through the year let’s see what can be done when a freeze is imminent.

Water the morning prior to a freeze event. Wet soils retain warmth better than dry. That heat will be re-radiated through the freezing night keeping your plant slightly warmer. Adding some mulch will aid this effort. Watering again the next day will break any ice formed in the soil. Keep in mind that prolonged saturation could be detrimental to root systems. Scout your plants regularly after using this strategy to ensure plant health.

Protect potted plants by bringing them indoors. Those that are too big to move should be padded with extra mulch, and clustered together when possible. Make sure to move them back in place when the warmth returns.

For those trees with graft points (i.e. Citrus), tree wraps may be used as protection. If you don’t have these, pile mulch around the base of the tree to insulate the graft. The idea here being that even if the branches above the graft succumb to the cold, the tree can rebranch above the graft thus keeping the desired fruit of that tree.

Finally, cover your plants.  Covers are more useful for frost than freezing temps but are better than direct exposure to cold air. Keep these off the plant’s foliage while ensuring they reach all the way to the ground. Think ghosts over lollipops. Taking them to the ground will capture any heat radiated out of the soil overnight. The addition of lights underneath the cover can help keep that area a little warmer. Be very cautious when doing this as too much heat under the cover could be dangerous.

Covered landscape bed

Plants covered above the foliage, and to the ground. UF/IFAS Photo

You may see some nurseries apply irrigation via sprinklers through the freeze as protection. While this method does work, it requires some specialty equipment. Additionally, you’ll need to apply the water prior to the freeze setting in and continue until the temps return. It not a practical solution for homeowners.

Once the cold passes, keep an eye on your plants. Wait until you see new growth before pruning damaged plant tissue. If in doubt you can slightly scrape the bark. If the cambium beneath the scrape is green, it is still alive.

For more information on cold protection or any other horticultural topic contact you local UF/IFAS Extension office.

 

Let’s Scout the Garden

Let’s Scout the Garden

One of my favorite ways to spend the morning lately is in the garden drinking my coffee. There’s no intended purpose, other than to look and see what I can find. I always end up finding something interesting! Scouting your garden does not have to be a formal process, but it is more effective when done regularly. This can help to avoid the “it happened overnight!” phenomenon that we hear frequently. Pests and diseases do not typically cause damage that quickly. Regular scouting helps you notice small symptoms before they become big problems. Training your brain to notice these small changes happens over time with your scouting, but just like any new skill, you need to practice! Give it a chance and watch the tiny world open up around you. Come scout the garden and see what we find.

In this photo you can see a close up of the mummified vs. regular aphids. For more information on parasitic wasps and other natural enemies see: https://edis.ifas.ufl.edu/publication/IN120

I noticed some wrinkled leaves on the new growth of a zinnia. Wrinkled new growth can be a sign that a piercing-sucking insect is causing damage. Turning over the leaves revealed aphids, a common culprit on zinnia. In this photo we can see aphids in a few different life stages. Importantly, we also see that some of the aphids are serving as food for beneficial insects. These mummified aphids are the ones you see with tan, golden bodies that are larger and more round. A small, parasitic wasp larvae, is living inside the aphids body– using it for protection and food until it is ready to emerge. These are good signs of a healthy working ecosystem and they can help keep aphid populations in control. This helps me to know that there are aphids in my zinnias, but that I don’t need to do anything about them right now. Natural predators are at work and can be more effective than chemical applications at this time. If you need help identifying insects in your garden, reach out to your local extension office. Not all insects on our plants are causing harm; and some are actually helping decrease pests.

 

I don’t always find pests in the garden. Sometimes I realize the irrigation timer was turned off or I take a really pretty picture for my instagram story (see below). These are still wins in my book! Remember that your landscape is an entire ecosystem and you are a part of it. It’s a great practice to walk around and take an intentional look at your plants when you get the chance, you may see something cool!

Improve Butterfly Habitat with Trees

Improve Butterfly Habitat with Trees

Many gardeners enjoy plants that attract butterflies and there is no shortage of beautiful flowering plants to supply nectar for all our pollinators. One critical part of making habitat for butterflies that we may need to improve upon is supplying plenty of host plants for butterfly development. While we enjoy the flight of a butterfly through our garden, we really want to offer features that keeps them around.

Your landscape likely includes a few host plants and maybe you even have a citrus tree or plant parsley every season. What many people don’t realize is how many native trees serve as host plants for butterflies.  Some of these plants like specific environments while others can grow in a wide variety of habitats.

The Black cherry (Prunus serotina) and Cherry laurel (Prunus caroliniana) serve as host to a large number of butterflies. A more well know species that uses the native cherries for development is the Tiger swallowtail. Although we might consider these trees weedy, they can serve as hosts to hundreds of species of butterflies and moths along with providing berries for wildlife.  The black cherry will be deciduous while the cherry laurel is evergreen. Both have flowers in late winter or early spring.  Just be aware that the cherry laurel fruit can have some toxicity in different developmental stages.

Yellow form of the Tiger Swallowtail. Some females can also have mostly black coloration to prevent predation. Photo: Beth Bolles, UF IFAS Extension Escambia County.

The Winged elm (Ulmus alata) is gaining in popularity as a landscape tree. The Question mark butterfly will lay eggs on plants under the elm and then caterpillars crawl up to feed on elm leaves. The reason we don’t see this butterfly on flowers as much is that it also feeds on manures, carrion, and rotting fruit. Resting butterflies have wing patterns that make them look like leaves.

If you have a site with moist soil or can supply routine moisture, consider the Sweet bay magnolia (Magnolia virginiana).  It will attract the Tiger, Palamedes, and Spicebush swallowtails for development.  Flowers on the tree are not as large as those on Southern magnolia but you still have similar appearance and even a pleasant fragrance.

Palamedes swallowtail butterfly feeding on a porterweed. Photo by Beth Bolles, UF IFAS Extension Escambia County.

A couple of understory trees are the Pawpaw (Asimina triloba) and Sparkleberry (Vaccinium arboreum).  Look for the Zebra swallowtail to find the Pawpaw while the sparkleberry will serve as host to hairstreak butterflies.

Pawpaw also offers delicious fruit. Photo by Beth Bolles, UF IFAS Extension Escambia County.

Even though landscapes may have limited spaces for every host plant, we can preserve some spaces around borders for native trees. These plants will make a positive impact for butterflies and pollinators.

Summer is Too Hot for Lawn Herbicides

Summer is Too Hot for Lawn Herbicides

Hot, summer months are not the time to be using most lawn herbicides.

One issue is the heat of summer. Most lawn herbicide labels include statements such as the following. “Do not apply when temperature exceeds 90°F.” “Do not broadcast apply this product when air temperatures are above 90°F (85°F for St. Augustinegrass) unless temporary turf injury can be tolerated.”

Every year lawns are injured or killed because of lawn herbicides being applied when temperatures are too hot.

Summer is usually a rainy and windy time of the year. Many lawn herbicide labels include statements such as the following. “Allow 12 hours after application before watering lawn for maximum effectives on listed weeds.” “Apply only when wind is no more than 10 mph.” “Applying this product in calm weather when rain is not predicted for the next 24 hours will help to ensure that wind or rain does not blow or wash pesticide off the treatment area.”

It is critical to read and follow the label directions and precautions for any pesticide you use. Pesticide labels, including herbicides, include the following statements. “To the extent consistent with applicable law, the buyer assumes all risks of use, storage or handling of this product not in accordance with label directions.” “It is a violation of Federal law to use this product in a manner inconsistent with its labeling.”

Crabgrass plant growing in centipedegrass lawn

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

By the time summer arrives, many of the lawn weeds are mature, which means they are well established with extensive root systems. These mature, well-established weeds are more difficult to control. The same weeds are more susceptible to herbicides when they are small, young and not well established. Also, these mature weeds have produced countless numbers of seeds by summer. Most weeds are prolific seed producers.

A single crabgrass plant (a common summer lawn weed) can produce 150,000 seeds!

Applying a preemergence lawn herbicide in February to help prevent summer annual weeds such as crabgrass or applying a postemergence lawn herbicide during spring while the temperature is mild and before the weeds are out of control simply makes more sense than waiting until summer.

The best options now with lawn weed control involve continuing to follow good mowing practices, maybe hand removal of some weeds and just simply waiting for next February and spring to use lawn herbicides.

In the meantime, you may want to read the following UF/IFAS Extension publication on lawn weed control. https://edis.ifas.ufl.edu/pdf/EP/EP14100.pdf

SoilKit for Turfgrass Soil Sampling

SoilKit for Turfgrass Soil Sampling

You have probably heard about the SoilKit testing option that is available at local UF IFAS Extension offices.  Why would you want to use a new testing kit when the traditional soil testing kit is still available ?

UF IFAS Extension SoilKit is an option for those who want their turfgrass test results based on the latest evidence-based science. This is especially important when dealing with the application of phosphorus, a potentially polluting nutrient. If your soil measures adequate phosphorus for our warm season turfgrasses, you don’t want to add more.

UF IFAS Extension SoilKit. Photo by Beth Bolles, UF IFAS Extension Escambia County.

The good news is that UF IFAS turfgrass research has established thresholds for when nutrients like phosphorus are needed.  SoilKit is aligned with these thresholds and will only recommend nutrients based on the evidence-based science.

SoilKit does cost more than the traditional soil testing.   The convenience is that it includes postage so you put it directly in your mailbox for pickup. Another positive is that when you register your kit online, you can locate your home on a map and mark the square footage of the lawn area. When you get your results in a few days, there is no guess work. You will get a list of products and amounts to purchase for your size lawn.

SoilKit can be used to test other plant groups including gardens and shrubs. If you have questions about using SoilKit, your local Extension office can help.