Organic Treatment For Plumeria Rust

Plumeria Rust aka Frangipani RustSince we had such a mild winter here in Florida, some plumeria trees never went completely dormant and still have leaves with rust fungus. Normally, leaves will drop for several weeks in the winter and by the time new leaves emerge the rust is gone.  But that hasn’t been the case for some trees here in Florida, which have been putting out new leaves that keep getting infected. You want to get a handle on it before it gets out of hand.

First, pick off all of the leaves that are heavily infected. Throw them in the trash along with any that have dropped on the ground. Mix 1 heaping tablespoon of baking soda and 1 tablespoon of Neem oil(or other horticultural oil) in 1 gallon of water, along with a few drops of dish soap (soap helps it stick to the leaves). Using a tank sprayer, spray the entire plumeria plant or tree once a week, especially the new growth. Make sure to spray under the leaves. This should keep the rust under control.

Note: When it gets warmer, do not spray in the heat of the day – Neem can burn foliage. Neem oil is available at Ace Hardware, Home Depot, Lowe’s and other garden centers.

Fertilizer Ban – Research Your Replacement Products

Some of you here in Florida, and other parts of the country may already know there is are fertilizer bans in certains places and manufacturers are phasing out products that contain phosphorus. Here in Pinellas County fertilizers containing nitrogen and/or phosphorus cannot be applied to lawns or landscape plants from June 1 to September 30.

That means some your long time favorite fertilizer and other products that contain phosphorus have been removed from the shelves of Lowes, Home Depot, etc. and replaced with phosphate free products. First off, you may still be able to find your favorite fertilizer at smaller stores, like ACE and such. But run, don’t walk. Usually, when a product is deemed not fit for public consumption smaller stores take longer to run out of their stock and it remains on the shelves for months, even years(remember Diazinon?) . However I have heard that in the fertilizer ban case, county officials are actually going to stores and enforcing the ban.

So, you realize it’s too late, you’re stuck with the alternative, whatever that may be. Many products are being replaced with those we are not familiar with, made by companies we’ve never heard of. Before you just put in your cart and take it home, do some research. Don’t just assume that because the retailer put it on the shelf where the good stuff used to be, that it’s okay to use, or that the application or results will be the same. Read the labels carefully, and ask your friend or neighbors if they have used it.

Case in point: The St Augustine lawn fertilizer I have used for years, was removed from the shelves and replaced with something I never heard of. But it was the only alternative so I took it. I read the application method – same sthe other stuff. That evening I set the spreader, put it down, watered it in. Just like the other stuff. Then to my horror the next morning. there were orange streaks from the iron all over my driveway. The old stuff never did that. Yes there is rust remover for driveways, and yes it removes the stain – and leaves a bright white streak. So if you prefer orange streaks to white, don’t bother. I’m sure there was some tiny mention on the bag about not getting the product on walkways, etc. It was probably on the old stuff too. On the bright side, the lawn is nice and green.

Protect Your Plumeria From Freezing Temps

Old Man Winter is a bit early this year. We do not normally see freezing temperatures along the Tampa Bay gulf beaches, especially this early in the season. I can only recall freezing one time in the last 10 years (last January). So much for global warming.
Special care must be taken to protect Plumerias if freezing weather is expected. For mild climates in southern Florida or Texas (zones 9 or higher) covering them with freeze cloth or wrapping them with Christmas lights a couple nights a year may be all that is necessary. Small potted plants can be easily moved indoors.

In cooler climates plumerias will need protection all winter, or as long as freezing temperatures are possible. Plumerias are dormant during this time and can be dug up and stored bare root in a garage or basement, as long as it is dry. They will most likely be defoliated already, but if any leaves remain remove them before moving inside to save yourself from having to pick them up later. They do not require light, food, or water during this time.

When spring approaches they will begin to wake up. Their tips will become shiny – a sign that leaf growth is about to begin. As long as there is no danger of a freeze, they can be moved back outdoors.
A note of caution – If you store your plumeria indoors, be carefull to store them upright, do not stack them. Otherwise the ones on the bottom of the pile may rot, due to poor air circulation.

What Does Cold or Freeze Damage Look Like?

I often get asked what to look for when it comes to frost or cold damage to plumerias. Here is a photo taken of a damaged plumeria branch after “the big freeze” in Florida. Damaged branches will turn brown, and in some cases the tip will turn black, as in this case. The black tip is rotted plant tissue and must be cut off to prevent further damage to the plant. If the branches are merely browned, but hard and firm with no soft spots, no action may be necessary. But, check it frequently to make sure there is no further damage.

To treat an affected tree: With a sterilized cutter, cut below any black or soft mushy area until you get to clean white growth. The cut surface should not show any brown spots. These areas can continue to rot, and travel down the plant and kill it. Treat the cut with a fungicide.

This was the first year I had cold damage. We live near the gulf and don’t usually see temperatures as cold as inland, but this year has been very unusual. The gulf temperatures are lower than usual this year and not providing the usual insulation against cold snaps. For the first time, our outdoor digital thermometer registered below freezing on a few nights. Damage was not limited to plumerias, our Christmas” palms suffered greatly as well. I am looking forward to spring, it can’t get here soon enough.

What To Do If Your Plumeria Has Frost Damage

Many of you in Florida have experienced cold damage to your plumerias for the first time due to the record breaking cold this year. How do you know if you have damage? If the branch tips are mushy or black they have been damaged by frost or freezing. Cut the tips back until you get clean white wood to prevent the rot from spreading down the tree. Try to cut just above a leaf node. New branches will grow in the spring.