Gardening with Gary




Gardening Advice from an Expert

Plumeria

Q. Can you tell me the light, water, and soil requirements for plumeria? It will be kept outdoors in a pot. I got it from a garage sale. There were tons, in all colors. I have no idea why I bought it, because my yard is simply full as it is!

A. Plumeria are a true tropical flowering tree. They are well suited to Texas and the Gulf Coast climates from April through October, but usually must be protected from November through March. Since plumeria have a natural dormant period, this can correspond very conveniently to an indoor storage period during the winter months. Plumeria can be grown in containers, in the ground, or in containers sunk in the ground. During the months of active growth, ample sun, food and water are essential. Healthy plumeria will bloom regularly and profusely when they receive at least 6 hours of full sun per day. Plumeria are heavy feeders and will bloom and grow vigorously with an ample amount of the proper foods. Plumeria love lots of water, but cannot tolerate wet feet, so they must be planted in fast draining soil or in beds with adequate drainage.

IN THE SPRING

When the night time temperatures begin to remain above 50 F, plumeria can be brought out of winter storage and "encouraged" out of dormancy. Due to conditions of storage, some root loss and desiccation of branches can be expected, but is not cause for alarm. This is the time to feed, water, top-dress, and/or repot. Since the plant is dormant, it will be minimally disturbed by repotting or root pruning if necessary. Repotting and root pruning are optional and are performed as with any other container grown plant. Top-dress by scraping off the loose soil and dried up roots from the first inch of soil in the pot. Replace the removed soil with a mixture of compost and well composted cow manure, but do not pack it in. Then feed and water thoroughly with a fertilizer such as "Super Bloom" or "Carl Pool's BR-61". If desired, there are specialty plumeria foods that can be used as well. Place the plant in a warm and sunny location. Some people like to sink the container in the ground. This promotes more vigorous growth, provides support, and prevents it from blowing over. Plumeria tips are fragile and easily snapped off when the plant blows over.

IN THE SUMMER

For plumeria, summer has arrived once a lush growth of leaves has developed. Many will bloom before developing leaves, others will not. Once the leaf growth has developed, the summer regimen of care can be followed. As mentioned before, plumeria are heavy feeders. However, in order to discourage excessive stem elongation and to promote flowering, fertilizers low in nitrogen and high in phosphorous are recommended. Once again, "Super Bloom" or "BR-61" are excellent choices. Keep a plumeria healthy by feeding every other week, and by watering as necessary. During exceptionally hot periods, plants in aboveground containers may need thorough watering as often as twice a week. Drooping leaves can indicate a thirsty plant. As with all plants, check the soil before watering. If it's dry for the first couple of inches, water it thoroughly. Certain varieties of plumeria do find our Texas heat a bit much for nominal blossom production. If this appears to be a problem, move the plant into a "shifting shade" location for better flower production and lasting quality. As the days begin to grow shorter during August and September, some lower leaf yellowing and drop is normal. Some varieties will attempt a fall bloom cycle if we are lucky and the weather cooperates. Plumeria can still be blooming into November and December! But watch out, an early frost can damage or kill the plant.

IN THE FALL

For plumeria, Fall begins the first of October. Stop feeding and reduce water to encourage the plant to go into its natural dormant period. It is difficult to predict the weather, and, therefore, it's difficult to give a date by which your plumeria should be safely stored for the winter. By all means, if temperatures are expected to fall into the 30s, the plant should be protected. Many varieties can be damaged or killed by temperatures in the low 30s or upper 20s, even for a few hours.

IN THE WINTER

During the winter, plumeria require very little care. In fact, "winter care" could be considered "winter storage" rather than care. Before storage, the plumeria should be defoliated. To date, the best technique for this is to cut each and every leaf off the plant at a point about one inch out from the stem. If you do not defoliate, the leaves will yellow and fall off during storage, and provide a good environment for pests and fungus as well as make a mess. Store the plumeria in a cool, dry, dark, and ventilated area such as a garage or storage shed. Temperatures should not be allowed to fall below freezing in the storage area. During exceptionally cold periods (i.e., below 25 F outside), a small supplemental heater may be required. A cool greenhouse is not recommended for plumeria storage. Some people suggest not watering them at all for the entire winter, but a small monthly drink probably does more good than harm, especially if the branches are getting desiccated.

Milton Pierson, Research Committee
The Plumeria Society of America, Inc
http://www.ruf.rice.edu/~miltonp/plumeria/PlumeriaCare.html#start

Member Debbie writes~
Recently I received a small plant that is called frangipani. I was told that they make Hawaiian leis with the flowers. Would you please tell me how much sun and/or shade does this plant need outside? I live in Florida, Zone 9-10.

A. First of all, thanks so much for including your zone. More and more people would like to know where the plants are being grown and which do well in their zone.

Frangipani [Plumeria] are amongst the worlds easiest plants to propagate, grow, and flower. There are not many other plants that give so many months of flower for so little effort. They are a true tropical flowering tree. They are well suited to Texas and the Gulf Coast climates from April through October, but usually must be protected from November through March. Since plumeria have a natural dormant period, this can correspond very conveniently to an indoor storage period during the winter months. Plumeria can be grown in containers, in the ground, or in containers sunk in the ground. During the months of active growth, ample sun, food and water are essential. Healthy plumeria will bloom regularly and profusely when they receive at least 6 hours of full sun per day. Plumeria are heavy feeders and will bloom and grow vigorously with an ample amount of the proper foods. Plumeria love lots of water, but cannot tolerate wet feet, so they must be planted in fast draining soil or in beds with adequate drainage.

IN THE SPRING

When the night time temperatures begin to remain above 50 F, plumeria can be brought out of winter storage and "encouraged" out of dormancy. Due to conditions of storage, some root loss and desiccation of branches can be expected, but is not cause for alarm.
This is the time to feed, water, top-dress, and/or repot. Since the plant is dormant, it will be minimally disturbed by repotting or root pruning if necessary. Repotting and root pruning are optional and are performed as with any other container grown plant. Top-dress by scraping off the loose soil and dried up roots from the first inch of soil in the pot. Replace the removed soil with a mixture of compost and well composted cow manure, but do not pack it in. Then feed and water thoroughly with a fertilizer such as "Super Bloom" or "Carl Pool's BR-61." If desired, there are specialty plumeria foods that can be used as well.

Place the plant in a warm and sunny location. Some people like to sink the container in the ground. This promotes more vigorous growth, provides support, and prevents it from blowing over. Plumeria tips are fragile and easily snapped off when the plant blows over.

IN THE SUMMER

For plumeria, summer has arrived once a lush growth of leaves has developed. Many will bloom before developing leaves, others will not. Once the leaf growth has developed, the summer regimen of care can be followed. As mentioned before, plumeria are heavy feeders. However, in order to discourage excessive stem elongation and to promote flowering, fertilizers low in nitrogen and high in phosphorous are recommended. Once again, "Super Bloom" or "BR-61" are excellent choices. Keep a plumeria healthy by feeding every other week, and by watering as necessary.

During exceptionally hot periods, plants in aboveground containers may need thorough watering as often as twice a week. Drooping leaves can indicate a thirsty plant. As with all plants, check the soil before watering. If it's dry for the first couple of inches, water it thoroughly. Certain varieties of plumeria do find our Texas heat a bit much for nominal blossom production. If this appears to be a problem, move the plant into a "shifting shade" location for better flower production and lasting quality. As the days begin to grow shorter during August and September, some lower leaf yellowing and drop is normal.

Some varieties will attempt a fall bloom cycle if we are lucky and the weather cooperates. Plumeria can still be blooming into November and December! But watch out, an early frost can damage or kill the plant.

IN THE FALL

For plumeria, Fall begins the first of October. Stop feeding and reduce water to encourage the plant to go into its natural dormant period. It is difficult to predict the weather, and, therefore, it's difficult to give a date by which your plumeria should be safely stored for the winter. By all means, if temperatures are expected to fall into the 30s, the plant should be protected. Many varieties can be damaged or killed by temperatures in the low 30s or upper 20s, even for a few hours.

IN THE WINTER

During the winter, plumeria require very little care. In fact, "winter care" could be considered "winter storage" rather than care. Before storage, the plumeria should be defoliated. To date, the best technique for this is to cut each and every leaf off the plant at a point about one inch out from the stem. If you do not defoliate, the leaves will yellow and fall off during storage, and provide a good environment for pests and fungus as well as make a mess.

Store the plumeria in a cool, dry, dark, and ventilated area such as a garage or storage shed. Temperatures should not be allowed to fall below freezing in the storage area. During exceptionally cold periods (i.e., below 25 F outside), a small supplemental heater may be required. A cool greenhouse is not recommended for plumeria storage. Some people suggest not watering them at all for the entire winter, but a small monthly drink probably does more good than harm, especially if the branches are getting desiccated.

Since a defoliated plumeria takes up considerably less space than one in full leaf, they can frequently be stacked two and three high in the storage area.

http://www.ruf.rice.edu/~miltonp/plumeria/PlumeriaCare.html#start

The Plumeria Society of America

If you have any further questions, please do not hesitate to contact:

support@frangipani.tv

Q. I'm repotting that plumeria today. They are in those tall black 6" or 8" pots that you get plants in from the nursery. When I transplant it, am I right in thinking it should go into a pot not too much larger? I will eventually want it in a fairly large pot, but it has to gradually grow into a big one, right? If that's true, can you explain why you go up in small increments?

A. A very good point which has been confusing for years and has led to the premature death of millions of plants.

The proper proportion is nothing set in stone. You develop an eye for it the longer you garden and see how plants do. The telltale sign is to knock the plant out of its pot. Inspect the root ball. Does it feature roots which ring the exterior? Roots can actually strangle themselves as a result. That is why I strongly recommend cutting a line vertically, just deep enough to sever the fine roots on one side of the plant. This will encourage outer branching into the new soil mix. Such root ringing growth tells you it is time for repotting.

The reason why one pots up only one size at a time, usually measured in inches, is that the roots can only support so much soil mix. If you drastically increase the soil with the roots being a small size, then the pot will sit full of moisture which is not being drawn out by the roots into the plant above the soil surface. Too much soil with too little roots! The inability of the roots to absorb such a volume of water leads to moist soil and root rot.

For instance, if you transplant from a 6" to a 7" pot, then the roots have an appropriate amount of soil to be expected to fill and need. One step at a time leads to even, healthy growth.

Ilse writes~
My Plumeria were doing fine after your suggestions. They both bloomed this year and now have several new leaves and stalks. One of them I found suddenly has 2 leaves that are turning black for some reason. They have plenty of sun and I check the water situation with a moisture meter. They are fed as required, yet this suddenly happened. Any suggestions?

A. Plumeria require at least a half day of full sun to produce blooms. Plants should be allowed to dry out between watering, but excessive dryness will result in foliage loss. On the other hand, the growing medium should not be kept soggy wet. This can lead to the blackening of foliage as you have seen. A root rot leading to stalk rot and loss. Root rot can infect plants planted in a medium with poor drainage.

I recommend that you repot using a lighter potting mix and water less often. Add medium-sized perlite to your potting mix with good amounts of peat. Avoid a mix which contains soil, but if you must, make sure it is sterilized to kill off any fungi. I believe that is what you gave attacking your plant. But, lightening the soil, cutting back on the water, applying a fungicide coupled with maybe a little increase in heat and sunlight will end the attack.

Safer Fungicidal Soap or a fungicide containing benomyl will effectively control black fungus or rust. An environmentally safe alternative is a bath of approximately 4 oz. of liquid Ivory soap in a gallon of water.

A consistent feeding program will produce vigorous plants with large clusters of flowers from May through November. Plumeria require fertilizer high in phosphorus (the middle number). Super Bloom is an excellent choice. To keep the plant compact, avoid fertilizers high in nitrogen, the first of three numbers on the label. Feed the plant every other week, but discontinue feeding in September to allow new growth to harden prior to winter storage.

Michael writes~ I began growing a Plumeria plant indoors. About an inch of foliage grew. Recently I brought it outside, and the Plumeria seems to love the sunlight. It is summer and it gets at least 6 hours of sunlight each day. However, the leaves are turning out red. Instead of being green, the majority of each leaf is red. Are there some Plumeria who grow red leaves instead of green or is there something wrong with my Plumeria?

A. There are indeed red-leaved hybrids of Plumeria and Frangipani. One is Plumeria rubra. It is quite beautiful and popular. Rainbow Frangipani and Plumeria Candy Stripe are two other hybrids found in searches. Whether there are pictures available, I am unsure. So, not too worry, it may be natural, but make sure that you are following a good regular fertilizer program since reddish purple leaves can be a sign of mineral deficiency in unhealthy foliage. Apply a food with trace elements at least monthly.