Garden Blog - Top Tropicals

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?.

Growing Exotic Adeniums

Exotic varieties of Desert Roses. Adeniums have many spectacular hybrids. The basic culture is very similar to orchids. A small pot with excellent drainage is a must. Adeniums do not like both over-watering or drying-out. There is a secret how to create a large swollen caudex: raise the plant a bit every time you re-pot it, so that the upper part of roots will be a little exposed. The plant will form more roots that will go down.

To make your plant develop a large swollen base/trunk, you'll need a good quality fertilizer. Fertilizer requirement for swelling up trunks is also used to increase flowering. It shouldn't be too high in nitrogen, the middle number should be the highest (similar to 10-50-10). Never apply fertilizer directly on roots and do not liquid feed when a plant is thirsty: always water first slightly to avoid root burn and leaf drop. Do not wet leaves. Adeniums need lots of light for heavy flowering.

Most hybrids and species start blooming in the spring when the conditions are warm and days get longer, and continue blooming through the fall and winter in warmer climates. Adeniums like a neutral to hard water. Acidic water tends to sour the soil too fast and may cause root rot. Water plants preferably in the early morning, and allow them to drink up throughout the day. Watering can be done daily to every few days. Never allow your plants to sit in a saucer of water, but don't let them to dry out too often - this causes adeniums to go into early dormancy.

Planting instructions for bare-rooted succulent plants. Position the plant in a pot, size of root system. Use only well-drained soil with high content of Perlite and/or sand (cactus mix can be used), water once and keep in warm (75-80F) place in filtered light. Do not water again until soil dries on surface. Once the plant is established and starts growing new leaves (may take a few weeks), gradually move it into brighter light. Then you can start fertilizing it.

See full list of Adeniums - plants and seeds.

Seeds germination in summer

Q: What is the best way to germinate seeds in summer? Should I keep trays indoors or put them outside?

A: Summer is the best growing season for plants, and for their propagation. Seed germination process of tropical plants usually benefits from warm, and even hot temperatures, so keeping pots with seeds outside in full or partial sun can be the best way. However some seeds may be more sensitive than others, or require slightly cooler or higher temperature for germination. These are a few tips that may help:

- For seed germination, use only well drained mixes, containing either peat moss or coconut fiber to retain moisture. Some succulents may require adding sand to the germination mix. You may also try our Professional Formula Seed Germination Mix.

- Large tropical seeds, like palms, or seeds of Fabaceae (Bean) family, can be grown in full sun. Their germination will benefit from higher temperatures (up to 90-95F). Make sure to keep soil moist. Cover them well, with 3/4 to 1 inch of soil.

- Fruit seeds (large size) should be germinated either in individual cells or small pots (3-4" diameter).

- Small to medium size seeds can be grown in so-called community pots. Seedlings can be separated after they establish their first roots.

- Tiny seeds should be planted closer to the surface, covered with only 1/4-1/8 inch of soil; some seeds require bright light for germination, so full sun will be a plus. Some small seeds like Ficus for example, prefer to be broadcasted on the surface, uncovered. Put containers with such seeds in bright shade, as you don't want the surface of the soil to dry out.

- Once your seeds sprouted, move them in filtered light - bright to medium shade depending on tenderness of the species. (Gingers prefer shade, while succulent sprouts can stay in brighter light). Regardless of water/sun needs of the species, all young sprouts and first leaves are sensitive to hot sun and may get burned or even killed. Once a baby plant has a few leaves and well-branched root system, you may start moving trays into a brighter light.

- Do not overwater young seedlings, keep soil slightly moist but not soggy.

See full list of available seeds.

Easter Lily Vine creates a fragrant privacy fence of virtually unlimited size

By Ron, South Florida. Easter Lily Vine (Beaumontia grandiflora) is a magnificent woody evergreen climber of unlimited growth potential. A branch of this vine will grow simply until you cut it. I have branches of up to 30 ft. and longer.

I've used two plants to turn a chain-link fence into a privacy screen that is 40 ft. wide by 10 ft. tall, but even a single plant can cover a much wider space if trained properly.

Easter Lily Vine's growth rate is moderate, so it doesn't require constant pruning to keep under control like other vigorous vines. I bought mine in 7 gallon pots, and planted them in the ground immediately. It took about 2 years to completely cover the fence. Since then, I prune it 3-4 times a year.

Keep in mind that these plants are heavy and require a solid structure as support. They twine by nature, but only around items with 3” diameter or more. Mine twined around a near-by lighting pole!

The absolute key in training Easter Lily Vine is to force it to grow horizontally. I recommend planting a young 3 gallon size vine in the ground diagonally, so it grows horizontally. Tie it no more than a foot above ground and let it grow a single branch until the end of the space you want to cover. Then force it to make a U-turn and let it grow the other way. See the following diagram for illustration..

See step-by-step full size pictures and the rest of the article...

Do-It-Yourself Support Structure for Dragon Fruit

This interesting do-it yourself project was sent to us by our customer from South Florida. Many tropical gardeners want to grow fascinating Dragon Fruit, and their most common question is - what kind of support I should use for this amazing fruiting cactus? We hope you find this information very useful. Happy Gardening!

Dragon fruit is a terrestrial/epiphytic fruit baring cactus, which may grow fleshy stems up to 30 ft high, given sturdy support. However, downward hanging or horizontal branches stimulate production of flowers at the tips of the branches. Commercial groves in different parts of the world use different method to achieve this. The traditional Vietnamese way is to train the plant into a “fountain”, which consists of a vertical central trunk about 8ft tall and a horizontal structure, such as a wagon wheel on top of it to support the horizontal branches (see picture on the right).

This picture served as my inspiration to build my own structure. I used five 4”x4” 10ft wood beams as the trunk, shaped as a cross. I attached the beams to each other with 10” long screws.

I dug a 2 ft deep 12”x12” hole in the ground and positioned the trunk inside, such that about 8ft are above ground. I covered it with several layers of burlap top to bottom.

The horizontal structure on top is made of four 4ft long 2”x2” wood beams and two 12”x12” wood plates to hold them together. I attached this structure to the top of the trunk.

I used old watering pipe to form two rings around the trunk to support the branches. Here is the result!... See step-by-step full size pictures and the rest of the article...