Fertilizing New Seedlings

Fertilizing seedling is very important to development and growth. Fertilization should begin soon after your seedlings grow their first “true” leaves. The first leaves that emerge from the seed are called the cotyledons. They’re rounded with smooth margins. The second set of leaves to develop is the “true” leaves. They look very similar to the foliage of the mature plumeria. When the first 2 sets of “true” leaves have fully emerged, it’s time to start providing your seedlings with nutrients and move your seedlings to the next stage in their care.

When the “true” leaves arrive, your seedling will have developed roots and need nutrients and sun to help convert the nutrients into plant food. There are lots of different potting mixes you can use, but I suggest ones that contain 1/3 pine bark, 1/3 peat, 1/3 perlite with Mycorrhizae. Potting soils with nitrogen will cause your seedlings to grow lanky. Lack of sunshine will also cause your seedlings to grow lanky

When you transplant your seedling into pots, it’s time to begin fertilizing with a balanced granular fertilizer containing micro-nutrients. I suggest slow-release Excalibur 11-11-14 or similar.

Suppose your seedlings get stressed from heat, too much rain, or insects. It’s beneficial to use a quick-release granular fertilizer or a liquid fertilizer. I suggest Excalibur BOOST 10-12-14 or Bioblast 7-7-7. You can use Excalibur BOOST every two months and Bioblast every two weeks. Choose a product formulated for use on seedlings.

If you haven’t started your seedlings in full sun, you will need to introduce them gradually. Begin by placing them in a shady spot outdoors for just a few hours. Slowly leave them outside for more extended periods and expose them to more sunlight until they are in full sun for at least 6 hours per day. This hardening off process is significant to young seedlings and helps them gradually adjust to brighter light levels, wind, and fluctuating outdoor temperatures.

NOTE: If you live in a region with extremely hot temperatures you may need to use shade cloth or less exposure to the hot sun.

Fertilizing New Seedlings

What does it mean when plumeria go dormant?

In gardening, the term “dormancy” refers to a perennial plant’s state of temporary metabolic inactivity or minimal activity. Plumeria generally goes dormant in response to adverse growing conditions, such as during the cold winter months when daylight is shortest and temps are below 50 degrees. Dormancy can also happen during a period of intense heat or drought. It’s important to remember that plants don’t die at this time, but are simply in suspended animation. While the leaves may fall off and above-ground foliage may look like it just a dead stick, life still lurks in the roots and core of the plumeria. The term “dormancy” isn’t often used to describe annual plants with a life cycle of a single growing season. Their biology does not include the mechanism for going dormant.

During dormancy, plumeria stop or slow down growth to conserve energy until better cultural conditions present themselves. This happens naturally as seasons and weather changes.

Plumeria Dormancy definition:

A period in which a plumeria does not grow, awaiting  necessary  environmental conditions such as temperature, moisture, nutrient  availability, etc.
A state of quiet, but temporary inaction. 
Quiet and inactive rest fullness. A state when organisms are in unfavorable conditions, and slow down their metabolic processes to a minimum to retain resources until conditions are more favorable. Plants may do this when their is a lack of water, while animals, such as the garden dormouse, hibernate, which is also a form of dormancy.

Growing Plumeria From Seed

Whether you plan on growing plumeria for pleasure or profit, you should know growing from seeds is a major commitment that grows bigger and bigger every year. Growing a plumeria from seed is the only way to produce a new cultivar. Typically it will take a plumeria 2-3 years to bloom and sometimes much longer. I believe only 1 out of 500 seedlings is worthy of growing to the point of being a commercially viable plumeria, but 1 out of 100 will be considered a keeper for most growers. And, it could take as long as 10 years to have enough product to bring to market. This is the main reason the newest cultivars cost more.

So, if you have the commitment and really want to make an incredible journey, I encourage you to grow plumeria from seed. It is a very rewarding journey and the feeling you get when you see YOUR seedling blooming for the fist time is a feeling you will never forget. It won’t mater if it is a world class plumeria flower or just a common white. The first is always special, but you will have that feeling of anticipation and excitement with every new seedling bloom.

Growing Plumeria from seeds has been my passion for many years. This year is no different, it’s time to try new things and have new successes and of course failures. Armed with all the data from past years, it an ongoing goal to determine what the best methods are for my growing environment, needs and budget. Some methods may be outstanding, but for me they are far too labor intensive. Some products may work great, but may be just too expensive to justify using. With all this in mind, the first thing to do is develop a plan for the next seedling project.

Plumeria Seed Selection 

IT’S EXTREMELY RARE FOR PLUMERIA SEEDS TO GROW TRUE TO IT’S PARENT(S). This is a very important fact to know. The good news, you can expect plumeria seeds to inherent some of its parent’s characteristics possibly going back 7 generations. The bad news is, most will inherent the less desirable characteristics. So the selection of which seeds you want grow is very important.

Selecting healthy seeds is imperative, if you are going to spend a lot of time and energy growing plumeria seeds, you deserve to have the best chance of success possible. 

Whether you are growing for fun or pleasure, you should select quality seeds from a trusted grower who will guarantee the pod parent. I would suggest you purchase a complete seed pod when possible or at least all the seeds in a seed pod. Be cautious of any seller who claims to know the pod and pollen parents, unless they are a very respected grower. Even though a plumeria seed typically does not grow true to its parent(s) you can improve the chances of getting an outstanding plumeria by knowing as much about a seed’s heritage as possible. Selecting seeds from a cultivar know to produce good seedlings is a good way to improve your chances of getting better seedling.

Viability Testing

A dormant plumeria seed certainly looks dead. It does not seem to move, to grow, nor do anything. In fact, even with biochemical tests for the metabolic processes we associate with life (respiration, etc.) the rate of these processes is so slow that it would be difficult to determine whether there really was anything alive in a seed.

Testing the viability prior to planting can be a resource and time saver. The viability of plumeria seeds can be checked by using one of several methods. 

Quick check: By simple feeling the seed to see if it feels firm and thicker in the center of the seed, there is a good chance it is viable.

Drop the seed in a bowl of lukewarm water and allow to set for several hours, as the seed takes on water and removes air it will sink in the bowl. If a seed sinks, there is a good chance it is viable.


If a plumeria seed is not allowed to germinate (sprout) within some certain length of time, the embryo inside will die. Each species of seed has a certain length of viability. Some plumeria seeds have been known to germinate after 12 years. It is best to plant within a few months of being dispersed. It is believed a few cultivars, such as Dwarf Singapore Pink, will lose viability as it dries out and should be planted as soon as possible.

Assuming the seed is still viable, the embryo inside the seed coat needs something to get its metabolism activated to start the embryo growing. The process of getting a plumeria seed to germinate is simple.

Plumeria seeds lack true dormancy. The seeds are ready to sprout. All they need is some moisture to get their biochemistry activated, and temperature warm enough to allow the chemistry of life to proceed.

Place the seed in soil with the fan part of the seed sticking up out of the soil and water well, keep the soil moist. The seed will germinate in a few days and you will seed the seed emerge within 5-10 days, sometimes longer.

Spread the seeds out on soil laying flat in a try and cover with 1/4″ of soil. Water well and keep the soil moist. The seed will germinate in a few days and you will seed the seed emerge within 5-10 days, sometimes longer.

Place the seed between two paper towels, soak with water, place the towels in a warm area. Leave until you see roots developing. Do not allow the towels to dry out, if the seeds start to germinate and then dries, it could stop it from germinating. As soon as roots appear, it is time to plant. You should see roots within a few days.

The seed cotyledon, which forms in the embryo of seeds before germination, stores food for the embryo. Along with the endosperm, the cotyledon nourishes the new growth of the plant. It is the part of the seed that emerges from the testa, or hard covering, during germination. It grows upward, turning into a set of seed leaves as the seed germinates, using photosynthesis to nourish the newly forming plant further. The seed leaves will fall off after true leaves form.

Initial Transplanting to soil & the First 3-5 Months of Growth

After true leaves form the growing needs change. As the seedling grows it will need more sunlight, warmth, moisture and nutrients. I believe the first three months of a seedlings life is the most important.

In 2016, I performed an experiment where I applied Excalibur granular fertilizer to a two-month-old group (Group “B”) of seedlings, I keep another group for control (Group “A”) without additional fertilizer, after 5 weeks I compared the groups. Group “B” had grown approximately 25% more in height and has substantially more roots. After 2 months, I added the same granular fertilizer to Group “A” and started treating both the same after that. The interesting fact is, after 10 months there was still an approximately 25% difference between Group “A”  and Group “B”. I will continue to track the growth of these groups over the next few year.

Care after transplanting to 1 gal or larger, approximately 3-5 Months

After approximately 3 months, it is important to start treating seedlings as young adults. For me this means, water as soon as needed, fertilize with micronutrients, organic matter, bio-stimulates, etc. that enhance the roots system and overall maturity of the plant. At the same time, I provide additional nutrients to the leave and tips to keep the plant healthy and pest free. The goal is to allow the plumeria to mature as much as possible in the shortest amount of time. It is important to understand the concept of “allow the plumeria to mature”. It is important to provide a balanced diet of nutrients, organic matter, bio-stimulates, moisture and heat without overdoing or under doing any one factor.

Right now I would say 99% plus of all plumeria seeds produced are pollination by nature. My overall goal is to grow seedling to bloom and establish a reliable seedpod parents to use with cross-pollination projects. I’m fortunate to have a company like Florida Colors Nursery with a real need to grow seedling for root stock and new plumeria for future sales. This provides a need for the 99% of our seedling that will not be outstanding enough to grow to a marketable size.  

When do you start fertilizing plumeria seedlings

Plumeria Seeds

Plumeria seed embryos typically contain two cotyledons and are grouped as dicots or dicotyledonous plants. It’s usually easy to tell which leaves are the cotyledons. As they are the first leaves the seedling produces, they will be the lowest ones on the stem, the ones to which an empty seed case often clings. They also won’t look like any of the other leaves on the seedling.

The cotyledons or seed leaves provide the seedling with nutrients for the first few weeks of its life, but when the seed leaves dry up and fall off, the seedling needs nutrients. Some people like to pinch off the cotyledons after the true leaves emerge. Unless those leaves are in the way, it is best to allow the seedling to decide when it’s done with them, or you may accidentally break its stem instead. Plumeria cotyledons are photosynthetic producers, as photosynthetic producers, cotyledons essentially can synthesize the organic nutrients it requires for growth through photosynthesis.

Fertilizers are frequently referred to as plant food, which is really not correct. Actually, it is the carbon dioxide in the air and the water in the soil, which in the presence of sunlight are converted into sugars and carbohydrates by a process called ‘Photosynthesis’, that do the actual feeding of the plant. Fertilizer is much more analogous to vitamins. The Nitrogen, Phosphorus and Potassium, and other trace elements contained in the fertilizers are necessary for cell division and enzyme processes that allow photosynthesis and growth to proceed. Photosynthesis is the process in which organisms use the energy from sunlight to produce glucose, a type of sugar, in addition to releasing oxygen. This glucose is the plant’s food.

Many methods and products are used by different growers to fertilize plumeria and plumeria seedlings. I’ve been experimenting with different plumeria seed growing methods and products over the last 20 plus year. The methods and products below are what I’ve determined to work best for me considering my growing conditions in South Florida (Zone 10b), so far.

The following is my current method for fertilizing plumeria seedlings for the first four months.

Over the last 5 years or so, I’ve been germinating and growing my seedlings outside in the full sun. (your weather conditions should be considered, not too hot, not too cold) Conducting experiments regarding when and how much to fertilize seedlings, some are complete some are still ongoing.

For the best results. so far, I use foliage feed with a liquid fertilizer at 1/2 strength for the first month or so. As soon as the seedlings have grown 3 or 4 real leaves I start spraying at full strength.

Fertilizing Plumeria Seedlings

  1. Fertilize with Bioblast 777 or similar as a foliage spray. If you use other balanced fertilizers, you should experiment, starting with 1/2 strength and increasing over time. When using a balanced fertilizer, I get better root growth and thicker trunks.
  2. When using a fertilizer high in Nitrogen as a foliage spray, the seedlings got very lanky very quickly. Lanky stalks and light green leaves can be a result of growing in shade or in a location with too little sun.
  3. When I using high phosphorus fertilizers as a foliage feed, I noticed the seedlings seem to shut down and didn’t put on as many new leaves. I suspect the seedling was having a hard time absorbing other nutrients.
  4. Micronutrients are important to healthy seedlings, so fertilizers I experiment with all contain micronutrients. 

I’ve also fertilizes from the bottom up method by setting the pot or plug tray in a container filled with nutrients. Similar to hydroponic methods. 

I don’t use granular fertilizers until I transfer to soil. I grow my seedling for the first stage in foam-injected peat plugs and then transfer the plug and all into a good soil mix.

I will transplant in pots when plenty of roots are protruding out of the plugs. This usually takes 2-3 months, depending on the time of year and weather conditions. The 2″ x 3″ plugs allow me to transfer directly into a 1 gal or larger pot mixed with ProMix without damaging the roots.

When I transplant into pots, I add granular fertilizer. I use Excalibur VI and apply twice a year. The season is almost all year long in South Florida Zone 10B.

Why Use Flexi Plugs?  –  Why Use ProMix?  –  Why Use Bioblast?  –  Why Use Excalibur Plumeria Fertilizer?