Information & Growing Conditions for Our Drosera Petiolaris Complex

The information provided is of Drosera petiolaris complex sundews and OUR growing conditions. 

Drosera petiolaris complex sundews, (also known as Woolly Sundews) are perennials plants that are from the tropical regions of Northern Australia. Its active growing season is in the hot wet spring and summer months when heavy rains are constant. The petiolaris complex consists of 13 tropical Drosera species:

  1. D. brevicornis

    D. broomensis
    D. caduca
    D. darwinensis
    D. derbyensis
    D. dilatato-petiolaris
    D. falconeri
    D. fulva
    D. kenneallyi
    D. lanata
    D. ordensis
    D. paradoxa
    D. petiolaris

Their main distinctive characteristic is a long petiole (leaves) that rosette from the center and ends with the tip being the trap (lamina). In most of the species, the petiole is covered with white non-glandular hairs, which can be either dendritic or simple. This can give them a white or green appearance depending on the amount of hair. In some cases, the hairs even appear silver. We sell a couple 😉 They could be long and thin, or short and wide. The lamina can also vary in different colors, width, oval, reniform or orbicular shape. They can be red, pale red, dark red, orange, pale orange, dark orange and white (clear).  The flower scape is 5 to 45 cm high, bearing inflorescence with a number of flowers, ranging from a minimum of 10 to over 70. The scape varies depending on species and can be more or less hairy. The flowers are white to pink, ranging from 0.5 to 2 cm in diameter. The size and amount of styles, the look and arrangement of anthers can vary depending on species as well. 

Our Drosera Petiolaris Sundew Growing Conditions

Petiolaris complex sundews aren’t hard to grow at all. They just have a few requirements to be happy. These are:

Temps: 75 – 100°F
These plants are from parts of Australia that are hot. So, of course, these plants love to be grown in hot weather. We grow out plants under 54 watt T5HO lights so heat isn’t an issue while the lights are on. Those temps are usually in the range of 85 – 100°F . It is when the lights turn off that temps begin to drop and we must supplement heat (this might not be needed if you live in a warm climate). We use a large submersible fish tank heater to keep water temps up and the roots nice and warm. If you have a small collection then a heat mat is recommended. Our fish tank heater is set on a timer and it turns on 15 minutes before our lights go off. The heater turns off 15 minutes before the lights turn on. We have noticed a better heat transition when using that time frame. Do not let night temps fall drastically. No more than 10 degrees from the time the lights went off is a great rule. We never let temps fall to or below 65°F . These plants will go into dormancy when temps fall below 65. Dormancy is not needed for these plants. They can be grown as tropicals and kept “awake” all year long. It is highly recommended they be grown as tropicals.  One good side note: Make sure any water added to the plants are at least room temperature. 

Humidity: 75 – 99%
These plants grow in humid conditions. The humidity range you choose between 75 – 99% is your preference. There are just a few things to consider when choosing. The less humid, the more hairs will grow on the leaves. This is considered because the hairs catch nighttime dew. Humidity drops once the sun comes up and the dew slides down the hairs which water the plant. Very low humidity can trigger a plant to go dormant. Most species only have hair when the plant is dormant. If you have a high humidity level then it is highly recommended you have good airflow. Our humidity range is 85-92 when the lights are on and 85-99 when the lights are off. We use two large USB fans set to low 24/7. We like that range because we think the plants look best with it. We also like the day humidity to stay closer to 85% when the lights are on and 92% when off if we are pollinating seeds. We also have noticed mold growing on traps with food when there isn’t good airflow with constant high humidity. We have heard of people successfully growing Drosera petiolaris complex in humidity as low as 50%. We do not, but if you do and if you get a plant from us, please start with humidity matching ours and slowly lower it to your desired range. We do not use any kind of humidifier to supplement humidity. We use a water tray to grow our pet complex within an enclosed space. That raises it enough to where we need to give constant airflow. High humidity does not produce more dew. It may look like it, but as soon as you take the plant out of their growing area, the dew will evaporate. Only intense light does.

Water: Distilled, reverse osmosis or rainwater
Since carnivorous plants live in nutrient-free soil, the water also must not have any nutrients. We have a very large setup that requires a lot of water. For this reason, we use local grocery stores that have water refill stations to fill 5-gallon containers. Before doing so, we check the water quality with a TDS meter to make sure the mineral content is low. Anything under 30 ppm’s is ideal. If you do not have a TDS meter and/or have a small collection, then Distilled, reverse osmosis or rainwater. Will work best. Distilled can be found at any grocery or pharmacy  store and usually cost .99 cents per gallon.

Watering and Pot Size: Tray method – Pot H 3.5″ x w 2.5″
We water our plants by the tray method. It is much easier and has worked very well. We fill the water to a half inch and then let the water lower to the very bottom of the pot, then refill again. Or pot sizes are H 3.5″ x W 2.5″. Those work very well for us. The roots of these plants grow very long, so if you are able to get pots that are 4″ or taller, that will work best.

Soil: Specially made for Drosera complex sundews
The soil we use for our pet complex sundews is sterilized and washed 3 times specially made by us and contain no minerals or nutrition. If you choose to make your own instead of purchasing our soil, then I would suggest a simple recipe. One parts each: peat and course 100% silica sand. Rinse each of those ingredients 3 times with distilled water to clean it of any impurities, bugs, etc. Mix, then microwave it until it is unbelievably hot. We use a meat thermometer to test the center. When the thermometer spins completely around twice or more, we know we are done. This will kill anything missed during the rinsing.   

Light: 54 watt T5HO
As mentioned above, we use 54watt T5HO lights to grow our Drosera petiolaris complex sundews. Mostly because we like the idea that they put out enough heat so we do not have to supplement it. I have seen great plants grown with L.E.D. and would use them if we lived in a warmer climate.  We recommend you slowly transition every plant you buy from us if you use L.E.D. We have many customers who do not transition them and have had great success. So it really depends on your experience and comfort level. Our lights have UV rays so any plant purchased from us can easily be transitioned to natural sunlight. Our lights sit 7 inches above the plants and always stay on 14-15 hours a day. The more intense the light, the more dew appears. Below is a spectrum chart of the lights we use: 

Our Drosera Petiolaris Complex Sundew Sources

Our Drosera petiolaris complex sundews come from these sources. Each species of plant will have its source mentioned as:

Source  – “Seed Grown” 

The large majority of our plants are grown from seed.  This meansthe plant grown isn’t an identical match to both parents. They most always appear the same but their DNA will not be the exact same. They are also the most fertile and the best to use if wanting to produce your own seeds. A seed grown plant will also not share the exact same DNA as another plant which came from the same lot of seeds (seed pod). They can pollinate each other but the amount of fertile seeds isn’t as great when compared to two plants from different generations.

Source – “Seed Grown Division”
In many cases, we save a plant from each species/hybrid. We then wait for that plant to divide and sell the divisions after they are established and actively growing. This plant will look 100% like the photo used to sell it. Each plant’s DNA from a division will match 100% to each other and from the plant in which they were divided.  They are not recommended to pollinate each other. We have heard of many cases where they were successfully used to “self pollinate” but we do not have any such personal experience. Since they are seed grown, they are fertile and can be used to pollinate other petiolaris complex sundews. 

Source – “Trade Division”
We also accept trades. In the event we love a plant from trade, we will grow it until it divides. The same rules of division apply as “Seed Grown Division”. The only difference is we did not grow the plant from seed: we traded for it from someone and have no idea how the person we traded from acquired the plant. This plant will look 100% like the photo used to sell it. It is not recommended to use it to pollinate another plant but to each their own. If you can do it, be my guest, and please try!

Urantia Carnivores®