Garden Blog - Top Tropicals

Date:

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.

Date:

Q: I live in California and about a month ago ordered several plants from you, including fruit trees (Carambola, Mango, Avocado) and flowering trees (Xanthostemon, Adeniums, Champaca, Ylang Ylang). They were all doing well until I tried to move them into full sun, when they got leaf burn immediately. Ylang Ylang was doing great in a shade, but I repotted it from 1 gal into 3 gal and it is drooping leaves now. It has been very hot (over 100F) and dry (humidity is less than 25%). Any suggestions?

A: Hot summer can be pretty challenging time for establishing new plants. These are some guidelines to make your summer gardening more successful and rewarding.

1. You can order plants at any time, but keep your eye on your local weather forecast and try to chose cooler periods to schedule your plant shipments. Here at TopTropcals we monitor weather at destinations, and we can also delay shipment per your request until more favorable conditions.

2. During hot Summer months, many plants are still OK to ship, and to be planted, many species are heat tolerant. It's usually safe to ship most succulents, including Desert roses and Euphorbias. Some fruit trees are pretty easy too, like Loquats, Mango, Eugenias. Many flowering trees can take heat: Acacias, Clusias, Jatropha, Sausage Tree, Plumerias and many others. Check our full list of plants suitable for hot and dry conditions. Most jasmines, including Jasmine Sambac and Trachelospermum make also a safe choice for hot weather planting.

3. Use shade cloth or simply white sheets to protect young plants and new plantings from hot sun.

4. When establishing mail ordered plants during hot weather, keep them in shade for longer period of time than average recommended 1-2 weeks. Give them a chance to establish really well. In areas with low air humidity, try to create a simple mist system. It can be purchased in your local Home Depot for only $20 and set up takes only 10 minutes! It makes a big difference and can help you save many plants from hot weather stress.

5. Although it may seem that during hot weather plants need more water due to high evaporation, be careful with watering, and check soil with your finger before watering - don't water if it is still wet. Combination of "hot and wet" can be as harmful for the root system as "cold and wet" during winter. Protect root systems from overheating: covering black pots with white cloth will work. Remember when temperature is above 90F, most of plants slow down their metabolism, which means roots slow down or even stop pumping water and become more vulnerable to overwatering. For the same reason, do not hurry to step up into bigger container if roots haven't filled yet the existing pot.

Date:

New Top Tropicals Video


Top Tropicals Video - Pesticide 101 Safe and Easy. Top Tropicals Plant Clinic with Robert Riefer (Certified Crop Adviser, ISA Certified Arborist). Many people are afraid of using harsh chemicals. We will discuss some pests you may find in your garden and what you can do about them, including using easy and safe household remedies.

Check out this video: Pesticide 101 Safe and Easy.

Stay updated with TopTropicals Videos by subscribing to our channel at YouTube.com/TopTropicals and get our latest video news of what's fruiting and blooming!

Date:

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.

Date:

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?.

Date:

Taking care of Soursop after shipping

Q: Since I have never grown a soursop tree before I need some pro help. My tree was delivered absolutely beautiful, leaves were a pretty green. I potted it and gave it a good drink of water and put it in a shaded area outside. Then the weather here became cool so I brought it in for a few days until the weather warmed, and it lost all the leaves. Is it in shock and will come around eventually? Will I be able to grow this tree indoors during winter?

A: Soursop - Annona muricata trees are very sensitive to temperature drops. This always causes leaf loss. You seem to be doing everything right. Do not water until soil gets slightly dry; keep it in bright shade. The weather should be good now with high temperatures and humidity rising. No fertilizer until the plant shows active new growth. Be patient with your plant, it should recover soon.

Soursop is an ultra-tropical tree and doesn't take any freeze. If you live in cooler climate, keep the plant in a pot (the good news is, Annonas in general have compact nature and are perfect for container culture). Bring the tree indoors during cold period, providing bright light.

We have very interesting article about growing and fruiting Soursop in apartment. Check out 4534 Tropical Treasures Magazine # 7.

Date:

Desert rose winter care

Q: I purchased several packets of desert rose seeds last year. I now have 45 very healthy seedlings some of them in bud. Almost all of my seeds grew but I lost most of them when I rook them in during winter. I did not water them for a month , kept them in their pots and set them by the window. they either dried up and died or rotted and died. I noticed when you send me grafted specimens that you bareroot them. Is this a better way to keep them inside in winter, bareroot? I hate to lose these plants come winter time. Pls advise me. I live in Houston, Tx. where we get temps below 40 degrees and sometime a day or more of freezing temps.

A: Thank you for your question. Rot is pretty common problem with Desert Roses. We monitor our Adeniums closely and have a special set up of watering environment and schedule, in dedicated greenhouses just for them. Nevertheless - every now and then we see a rotten caudex and can't help it to say "oops! over-watered!" These plants are very sensitive to environment changes, especially when it comes to a combination of water and temperature. These are a few tips that should help you to reduce risk of plant loss to a minimum:

1) 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%.

2) 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.

3) 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).

4) We do not bareroot adeniums for winter storage. They are not bulbs. Barerooting of this plant is recommended only during shipping. Adeniums can stay without soil for up to a week without hardly any stress, sometimes even longer.

5) 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!

Adenium Summer Sale: 20% off plants and seeds!

Date:

Hot novelty plant for hot Arizona

Q: What plants would you recommend for very hot and dry spot in front of my house that gets full sun all day long? I live in AZ, we recently had a couple good rains but this is going to be it for a long time. It gets so hot during the day that every plant I tried didn't make it. We have a few nice orange trees growing well but I would like to plant something compact, colorful and hopefully fragrant if there is such plant.

A: There is a perfect small size plant for you that is extremely fragrant and yet will be thriving in these conditions. It is the famous Jasmine sambac. It will appreciate dry air of Arizona and will bloom profusely for you in full sun or in partial shade. It doesn't mind heat at all.

For colorful accents, a proven winner is Crown of Thorns - Euphorbia millii. New giant size flower varieties were recently selected in Thailand, and we just received a great selection, look at the colors! These plants don't mind hot sunny location at all. The more sun, the better the bloom! Small plants need regular watering until establish, then once they start developing, they will require less water.

Giant Euphorbia flowers from Thailand are 4-5 times bigger than regular flower euphorbia. Diameter of the flower is around 2". Compare giant flower to normal size - picture on the right.

See full list of plants for hot and dry spots.

Date:

Erblichia or Flor de Fuego - Apricot fragrance and sunny color

Q: I saw this wonderful flower Flor de Fuego on your website and I would like to buy this plant. I am wondering how big this tree will grow and how long will it take until I can smell the lovely flowers? I have a big garden and not much space left, but I still have a few spots available for smaller trees. Also any special care info will be appreciated.

A: Flor de Fuego is a small tree and will fit in any small yard situation. It is very rare in cultivation. This is the newest, most exciting tree to be introduced in the last decade. It said to be one of the most beautiful flowering trees in Central America. It has long narrow leaves and large flowers 6-8" across that smell like apricots. It blooms from late fall through early winter and sometimes through spring. Normally it starts blooming in 2-3 years after planted in the ground. Surprisingly for such a delicate plant, it tolerates poor soils. Once established, it doesn't require any special care other than regular watering and fertilizing during hot months. It does take some effort sometimes to make the tree happy in its new habitat. After planting in the ground, keep your eye on irrigation schedule and do not let soil stay wet, young trees don't like wet feet. In natural habitat, the plant prefers to have a dry period that is beneficial for profuse blooming.

See full size picture of Erblichia tree in full bloom

Click here to buy Flor de Fuego

Date:

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.