Overwintering Adeniums outside of tropics

Q: We bought several adenium plants from you. We are moving to the Denver area of Colorado. How can we make sure the plants survive? Should we use a green house?

A: Adeniums are perfect container plants, and house plants. They can be easily grown outside of tropical climate. During winter, Adeniums drop leaves and go into dormancy which makes it easy to keep these plants in a dormant stage in a warm location of your house, or possibly even in well-lit spot of garage (with a window), with temperatures above 50-60F.
Here in South Florida, during time of cold, when chances of freeze are high, we move our own Adenium collection into lanai, with plastic sheet protection around lanai.

In colder climates, Adeniums can be kept indoors as house plants during winter. There are some requirements/tips for you:

• Temperature. Move Adeniums indoors when temperature starts dropping below 45F.
• SUNSHINE. Use SUNSHINE boosters to improve cold resistance of Adeniums, and essure healthy plant throughout winter. SUNSHINE-BC formula is specifically designed for plants with caudex, and bonsai.
• Water. Reduce watering to minimum, especially when plants drop leaves - this means they went into dormancy. Once a week light watering is enough. Water very carefully during cooler months. When it is hot (85-100F), excessive water usually won't harm adeniums: it will be partially used by a plant, and partially will evaporate. Especially be careful with water when temperatures drop below 65F - then tropical plants simply stop growing process and go dormant. Once adeniums start losing leaves, this is a sign to reduce watering to once a week to once a month, and in very small quantity (couple tablespoons per pot).
• Light. Bright light is not necessary, but do not keep them in dark either, even if all leaves dropped. Good light is necessary to maintain healthy stems and caudex. Keep in mind, the less light, the less watering too. Ideal spot is a windowsill, however if your space is limited and all windows occupied by other "leafy" plants, location close to window will be enough as long as watering is reduced, to avoid rot. We keep our big collection specimens on a roofed porch during winter, where level of light is very low. Last winter we haven't lost a single plant due to low light. They take shade pretty well considering minimum or no water. However bright light is always better - it creates healthier environment for a plant. We all know about space limitations for our large collections, especially in winter. So if you can afford a bright spot for adenium during winter - the plant will be lucky!
• Soil. Use only well drained mix with much higher content of perlite than you would use for most tropical plants. For adeniums, we use mix with 30-40% of perlite in it, while regular mix has 10-15%. Adeniums like alkaline soil, unlike most of tropical plants (hard to say what else likes alkaline... Ficus for sure!). This means, regular mix with high content of peat moss may cause root rot. To increase alkalinity, you may add dolomite. Here in Florida where we have natural supply of shell rock handy, it is easy to add some shell to a potting mix (shell sand, rather than quartz sand). We always add a few large shells on top of a pots with a big specimen. Besides increasing soil pH (making it more alkaline), shells look very decorative.
• Fertilizer. No fertilizer until Spring when plants start showing new growth and new leaves.
• Move your Adeniums outside in Spring, when chances of freeze are zero. More sunlight and air circulation is beneficial for breaking the dormancy and providing plants with a quick growth start.

Growing by the sea

Q: Please recommend me some interesting plants that can grow on my waterfront property and can withstand some salt wind. All my neighbors have Sea Grape trees and bougainvilleas, and I want something different and special. I would love to have some colorful or fragrant flowers, or fruit around my paradise home.

Q: Considering your neighbors successfully grow Sea Grape (Coccoloba), and Bougainvilleas, you have a mild, frost free climate. There is a number of spectacular and useful tropical plants that are salt tolerant. Orchid Trees - Bauhinias, Poincettia - Delonix, and Geiger trees - Cordias, are very showy flowering trees. For large size bushes, try Dwarf Poincianas - Caesalpinias, and Scarlet-Coral Erythrinas. Frangipani - Plumeria, come in different colors and bring you perfume fragrance from Hawaii. And of course, Desert Roses - Adeniums, can be grown and showy specimens anywhere in your yard, both in the ground or as potted bonsai.

Most palms, especially popular Coconut Palm, source of tasty fruit and drink, are highly tolerant to salt breeze. If you are looking for something that nobody has, Lipstick palm, or Sealing wax palm - Cyrtostachys lakka, is definitely the most spectacular palm you can find. It is a stunning feather palm that develops a brilliantly red trunk. Palm is originally from Malaysia, but has been introduced to Costa Rica and other tropical areas of the world. Sealing Wax Palm seeds are very slow to germinate, up to a year, and large specimens are very rare and hard to find even in rare tropical plant nurseries. This palm will require a good overhead light, and constant warmth (above temperature 55F). It is definitely worth an effort to grow this beauty.

You may add more tropical accents to your landscape by the sea with many varieties of showy heliconias.

See full list of salt tolerant trees.

Growing from seeds

Q: What is the best time to start tropical plants from seeds? Should I wait till summer?

A: Traditionally, people prefer sowing seeds in spring, especially temperate species for vegetable garden: tomatoes, peppers, cucumbers...

When dealing with tropical plants, you may want to start your babies indoors, providing additional heating when needed. If you keep your living space around 75F (ideal for many species), this is a perfect temperature to get your seeds started. Tropical plants are not like annual tomatoes that try to grow through the season as fast as possible. They may take time. So the sooner you start, the more chances to get small seedlings just in time when spring air outside is warm enough - at least in 70's F.

A great advantage of starting tropical seeds indoors is controlled temperature and moisture. In the plant world, environment extremes are not good for germination process. Mild conditions of your home or a greenhouse create better chances for successful growth. Seeds won't get overheated in hot summer sun, and won't get rotten because of a sudden heavy rain. Just keep in mind that some species require light for good germination. Using an old fish tank or covering with plastic wrap will help to keep constant humidity.

See full list of all seeds - all on sale, one day only!

Jungle on Windowsill 101

Q: I got a Jasmine Sambac and a Tahitian gardenia as presents, they are very cute plants with flowers and flower buds. I would like to be able to keep them alive and hopefully happy for a long time, but I don't know much about growing tropical plants, and I am not sure if my thumb is green enough to make everything right. What do they need? How much sun? How much water? What kind of soil? Sorry for all these (maybe silly) questions, but I want to keep them alive, please help! I live in Wisconsin and we had some snow again last week.

A: Growing tropicals is not a hard work, it is a lot of fun! These plants are actually a good starters for a beginner who wants to try growing tropical plants, no matter if you live in a mild frost-free climate, or up North where you can have these beauties as houseplants. Below are a few simple steps for you:

1. Read. Follow planting instructions included with your plants. Check plant names on the tags and learn more about them from our online catalog.

2. Soil. Plant in quality potting mix - it must be porous and well-drained, never use heavy soils (top soil or garden soil are no-no), in a pot exactly the size of the root system. You can step up your plants in the next size container once you notice vigorous new growth. Next size means: 4"pot can go into 6" pot, 6"pot into 10" pot, etc. Too big of a pot may create rotting environment, root system must fill the entire container to use all the moisture from the soil. Container must have good hole(s) for excess water to drain through. Put the pot in a saucer and get rid of excess water every time after watering.

3. Light. Most tropical plants require lots of light in order to produce flowers. If you ever visited Florida, remember the bright sun? - these are ideal light conditions for tropicals. Up North, provide as much light as possible: a bright spot on a windowsill of Southern or Western exposure would work the best. If the sun gets too hot in summer afternoon, you may shade the window a little bit with a sheet of white paper to avoid leaf burn.

4. Water. Keep soil slightly moist but not soggy. The best way is to wait until the top of the soil feels dry to touch - this is time to water again. Jasmines prefer to stay on a dry side; gardenias do not like soil to dry out - keep them slightly moist as long as soil is very porous and well-drained. The main reason of most problems with potted indoor plants is over watering. With experience, you will feel the right balance of moisture in the soil: the brighter the light, the more water is consumed by a plant; the less light, the less frequent you should water.

5. Trimming. In low light conditions, plants tend to become leggy. Trim branches as they become too long: the more you trim, the busier the plant gets. New growth promotes more profuse blooming in many species.

6. Fertilizing. Fertilize indoor plants with slow-release granulated fertilizer from march to November.

7. Insects. Check for insects at least once a month, especially underneath the leaf. If notice any problems (deformed leaves, residue, holes, or tiny insects) - clean the leaves/stems with a solution of warm water (1 cup), vegetable oil (2 table spoons), and a few drops of a dish soap.

8. Fresh air and air humidity. As soon as air temperature gets above 65F, bring your tropicals outside in the sun and fresh air: porch, balcony, outside in the yard. Air circulation is essential for your plant health. Bright light and high air humidity will promote vigorous growth, and lots of flowers for you to enjoy!

For more information on growing Tropical Plants 101, see Problem solving with potted plants - how can we help them?.