How to get Clerodendrum to bloom?

Q: My Clerodendrum thomsoniae is not blooming. Actually it is not doing much of anything except putting out weak growth and small leaves. I purchased this plant May 26. 2015. Over the winter it was in a heated sunroom, at night 60 degrees, where it received some direct sun from the skylights. I reduced the water to prevent excessive leggy growth. I don't see how this plant can take full sun or even part sun. Temps here in Raleigh NC are 80-85 degrees and 65-70 at night, at the moment. I figured I would gradually expose it to more direct sun after being in a sunroom but the leaves burn. I had this plant in San Jose many years ago where it did quite well, blooming with no special treatment. So thought I'd give it a try again. Any advice?

A: Clerodendrums are all time favorites, appreciated by both gardeners and house plant collectors, for their showy, fragrant flowers and very easy culture. When growing Bleeding Heart (Clerodendrum thomsoniae), a few things should be taken in consideration:

1) Temperature.Like most clerodendrums, this plant is semi-decidious outside of tropics and goes dormant in winter. It may lose some or all leaves if temperatures drop below 60-65F. It is not too cold sensitive, the plant can even take some light freeze. However when it is not hot and humid, it slows down metabolism. This means, water should be reduced during cooler months.

2) Light. This plant can grow in both sun and shade like most clerodendrums - this is the beauty of this genus. However like with all flowering plants, more sun promotes more bloom. In shade, it will grow beautiful dark green foliage (leaves will be bigger than in the sun) on the account of flowering; in full sun leaves turn lighter color and sometimes may even get unattractive "faded" look, but flowering will be profuse. Also remember that Arizona full sun is different than New York full sun. Here in Florida, Bleeding Heart can take some full sun, but if exposed to sun all day long, leaves often get sun burn.

3) Acclimation. Also called acclimatization - this is a process when a living organism adjusts to environment changes. Acclimation is always the case when growing plants indoors, even in a sun room. When Spring comes, and especially when we start taking outdoors those plants that have spent a few months indoors, light level increases dramatically, and this may cause leaf loss, and leaf burn. It is not necessarily a bad thing, it is just a mechanism of acclimation. Example: imagine yourself after living in a warm tropical climate, moving to a cold country. For a while your body will feel discomfort from "too much cold", while native residents may feel comfortable. We call it "My blood has thinned after living in Florida" - and this is a physiological fact. And vice versa, if you are a Northerner, moving to hot climate may be a challenge; it will take a while until you get used to hot and humid tropical summers. Same thing with plants: during cooler and darker period, their body (leaves and stems) becomes "winter type", with some serious chemical restructuring. Immediate environment change, like bright light and high temperature, causes a shock to those "winter cells", and as a defense mechanism, the plant gets rid of those useless "winter" leaves, replacing them with new "summer" leaves with completely new chemistry and metabolism.

From what you described, you know your plants, and you know what you are doing. You did everything right by reducing watering in winter and gradually moving the plant into brighter light. You still may see some stress, and this is normal. If you patiently keep changing environment slowly, eventually your plant will generate new healthy "summer" growth, it will also improve more vigorous root grown which will help the plant to establish better and to be stronger. You will see larger, thicker leaves, and definitely some flowers.

Plant Horoscope. Gemini Zodiac lucky plants: Anthurium and Philodenron

Gemini - 5/21-6/20. Ruled by the mutable, changeable planet Mercury (also patron of the art of medicine), Gemini is an AIR sign. Plants ruled by Mercury tend to have ferny or highly-divided leaves or stems (like the bronchi of lungs), hairy or fuzzy leaves (related to the cilia in the lungs), or subtle odors.

Gemini rules the lungs, shoulders, arms, and hands. Its plants help to strengthen the lungs and respiratory system, relax the nervous system, strengthen ears and hearing, the tongue and speaking, the vocal cords, lungs and thyroid, as well as the shoulders, arms, and hands. Gemini has so much going on mentally that they may need a little help to digest all the information they're constantly absorbing. Herbs that have clean, pure flavor not only help physical digestion, but assist spiritual and mental intake as well.

Gemini Zodiac lucky plants: Ferns, Blechnum, Tree ferns and Cyatheas, Fern Tree, Aralias, Jackfruit and Breadfruit, Paulownia, Anthurium, Philodendron, Philadelphus, Clerodendrums, Anise, Lavender, Myrtle, Nut trees, Macadamia, Ficus, Piggyback plant - Tolmiea menziesii, Aloe vera, Fig, Honeysuckle, Azalea, Mint Tree Satureja, Vitex, Ironwood, Mulberry, Osmoxylon, Acalypha, Allamanda, Aphelandra, Iboza, Ruda, Kiwi, Caesalpinia, Cyphomandra, Monstera, Kalanchoe, Magnolia, Oregano, Ocimum, Naranjilla, Zamia, Delionix, Acacias, Calliandra, Patchoili, Palms, Geranium, Grevillea, Eucalyptus.

For other signs information, see full Plant Horoscope.

5 secrets of propagation

How to propagate rare plants? It is exciting and fascinating process - to be a Creator of a rare plant collection. Sometimes when you have a rare plant, you baby it and wish you could have at least two of the kind, just in case you lose one to weather conditions or an accident... If you lose one, it hurts! Plant collectors know the feeling - it is always a good idea to propagate a few more of the rare kind. Here at Top Tropicals we know that feeling too, and we want you to keep your baby plants alive and thriving, multiply them, share with others, and make our planet better - one plant at a time! Know your different plants, and different ways of their propagation. Ready for the secrets revealed?

1. Seeds. The most popular way and in most cases the most reliable. Also, a seedling has a strong, vertical root system (cuttings or air layers have shallow roots). However growing from seed is the only sexual method of propagation (vs other methods - asexual, or cloning), which means, some varieties don't come true from seed. Similar to a baby born from two parents, blonde mother and brunette father, can have either light or dark hair... or even red, genetically provided by the great-grand father! The most important factors of success when growing from seed are - well-drained germination mix (check out our Seed Germination Mix #3), and a combination of perfect temperature (high temperature 80-90F induces germination, but some species like it cooler!) and mix moisture level (can't stay soggy).

2. Cuttings. In most cases, works great as long as you know the secret for this method: clean (sterile) soil mix (check out our Propagation Mix #2), warm temperatures and very high air humidity (not moist soil, but humid air!). Mist house works well (see picture) with periodically controlled foggers (5-20 sec of fog every 5 to 20 min during light time - depending on species, and temperature), but simple clear plastic bag over a pot or tray works as well! Large leaves should be trimmed in half, or more, to eliminate extra evaporation, and soil should be only slightly moist, not soggy. Remember to use rooting hormone that not only improves rooting but keeps away fungus problems. You are welcomed to visit mist house in our facility, we will be happy to share experience.

3. Air Layers. From our experience, key to success with this method is patience. Most air layers take a few months to set root. Keep sphagnum moss moist, and create air layers only during active growth season - Sprint through Summer. Use rooting hormone.

4. Grafting. This method requires the most skills and experience but is not as difficult as it sounds. Plants can be grafted withing the same genus (e.g. one Gardenia sp. on another Gardenia sp.). There are many grafting manuals on internet. Try once, and you will get addicted to grafting! In many cases it is the most effective method. Especially when seeds not available and cuttings don't work with the species, while grafting works much faster than air-layering. The main secret in grafting is using the right type of graft, which comes with experience. Another important thing is keeping grafting parts and tools clean/sterile. Treat/clean surfaces with anti-fungicides horticultural soap (Example: Abound anti-fungal, Green Shield soap) and use rooting hormone.

5. Root divisions. All gardeners know that some plants are best to propagate by rhizome/root divisions, like Gingers, Heliconias, or Iris. And not everyone knows that some fruiting and flowering trees don't mind to reproduce by root divisions. For example, Jujube - Ziziphus jujuba, and Strawberry tree - Muntingia calabura, readily produce root suckers. Watch out for them and don't let them go to waist when spraying weeds. All time favorites, fragrant Clerodendrums also like this easy method of reproduction, especially C. bungei, C. philippinum, and many others.

Check out our Growing supplies section for professional soil mixes and drainage components that are so important in your propagation success. At Top Tropicals, we often use Coconut Coir for propagation. Good luck in your growing, and remember - if you propagated a few extra collectibles, Top Tropicals may trade or buy from you!

Spring time fun: fertilizing and pruning

Q: When is a proper time to start fertilizing my garden in Spring? Also, when can I cut back cold damaged branches? Should I wait until end of April?

A: As a rule of thumb, fertilizer can be applied during period of active growth, when a plant needs additional nutrients. With indoor plants, you can fertilize pretty much year round as long as the plant continues growing and not dormant. For in-ground tropical plants, start fertilizing when new growth appears. In subtropical areas, with cooler winter months, most tropical plants slow down their metabolism when temperature drops below 65F. Many of them become dormant, and may even lose leaves (especially deciduous plants like Annona, or Peaches/Plums). In spring, tropical plants wake up as soon as outside temperature stays above 65F for at least one week (including night time). Once you see new growth, this is a signal for you to start fertilizing.

As far as trimming dead branches - wait until you see new leaves completely opened up. This way you won't cut too much, as some parts of the plant may take longer to re-leaf than others.