Calathea lancifolia or rattlesnake plant, a perennial flowering plant from the Marantaceae family, is indigenous to Brazil.
It’s an evergreen plant and grows almost 30 inches tall with slim light green leaves 18 inches long with lovely dark blotches and purple underneath. It belongs to the group of plants popularly known as ‘prayer plants’ that fold their leaves in the night and unfold in the day, an activity called nyctinasty.
This happens by the plants changing the pressure of water in their nodes at the leaf‘s base along the stalk of the leaf. It is thought that this activity is directed towards these groups of plants aiming to follow the movement of the sun to get the best absorption of light. Under the appropriate conditions, the plant will produce yellow-orange flowers in warmer months.
These colorful lanceolate leaves are utilized in handicrafts such as basket-weaving, while broader leaves are used as food wrappers in Brazil. Their striking leaf patterns make them popular and widely cultivated houseplants.
This plant doesn’t like to be in direct sunshine, so it’s best grown in a shaded spot with indirect light. Excessive exposure to sunlight could cause quite a few problems like making leaves brown or crispy.
It needs frequent watering during its growing season without making it water-logged. This should be reduced during winter as the plant likes the soil to be a bit drier. While over-watering or under-watering can cause issues, generally these plants do require a larger amount of water.
This plant requires high humidity levels of around 50%, similar to its native habitat. Try to maintain a warm and moist environment around it all through the year. Misting it frequently might be a good idea as well as running a humidifier near the plant if maintaining high humidity levels is hard, this is particularly necessary for winter as arid air can make leaf tips brown.
The plant grows best in temperature ranges between 65-80 °F with a minimum low of 61 °F. It shouldn’t be placed near any vents or drafts as it is rather sensitive to fluctuations in temperature.
This plant requires well-draining yet moist soil. The best proportions of an ideal substrate comprise one part of perlite and three parts of a good-quality potting premix will work as well.
Repot the plant when roots start to fill out its present room, at least once a year. During this time, you can also think about dividing the plant and making many new plants. If this is the case, you can reuse the old one since the root-ball will become smaller.
There are two methods of propagating this plant – by dividing the plant or from cuttings, though the simplest one is by division. This is best done when you’re repotting the plant, as mentioned above.
First, the plant needs to be well watered so that the soil is loosened and moist. Then, take the plant and divide it into several sections, each section having roots as well as two stems/shoots.
Return the original plant to its home and plant the new sections into new pots using fresh soil and water them well. All that remains to be done now is making sure you water the new plants along with daily misting until the roots take and new leaves appear.
The other method of propagating the plant by cuttings involves taking stem cuttings with a minimum of 2 leaves on the stem. Remove any shoots along the base and plant in a new pot filled with suitable soil.
Place the cuttings near the original plant as it needs the same temperature and humidity levels for roots to set in and new leaves emerge. You can repot the new plant now if you wish. This will take a bit more time than the division method so be patient.
Feed it after winter ends with a solution of diluted balanced liquid fertilizer (a high iron content will give good results). Before feeding it, ensure the plant is watered well. Do not fertilize it in winter.
Remove dry flowers remaining on the plant and prune any old or damaged leaves to keep the plant looking good and healthy.
Spider mites can infest the plant, particularly if the soil is arid by under-watering or if humidity levels are too low. They are normally easy to deal with using insecticidal soap.
Brown leaf edges can either mean that the plant is receiving excessive exposure to direct sunshine or humidity levels are too low. Dry soil could also be a factor. Avoid baring the plant to direct sunshine and make sure to follow the correct watering schedule.
Low humidity can be raised by utilizing a humidifier, by frequent misting of the plant and using a humidity tray, or by growing the plant in more humid rooms such as kitchens or bathrooms.
If new leaves turn out to be lighter in color than older leaves, then this might be due to a low level of iron (iron chlorosis) or nitrogen. Increase the rate of fertilizing the plant and ensure that the fertilizer contains iron.
Do this for a few weeks and see if the plant responds and the leaves darken. If no change takes place, you may want to consider changing your fertilizer.
Leaf curl is frequently caused by under-watering the plant or by dry air (low humidity) making the leaves curl.
Older leaves can often become yellow – this happens naturally as they die off. But if this happens to several leaves simultaneously, particularly among lower leaves then over-watering might be the cause.
Brown tips on leaves are most probably initiated by dry air and low humidity levels. Increase humidity levels as suggested above to correct this problem.
Drooping stems is a serious matter caused by the plant getting over-watered in winter. This could ultimately affect and damage the entire plant and result in death if not corrected immediately.