So, Calatheas huh? For many of you it is a love-hate relationship, I know. Let’s change it and start to cultivate those ginger-related (!) beauties!
I never understood why calatheas are just casually on display in IKEA without a tag: “watch out, dangerous for the psyche”. It’s like they are lurking you into buying them for 9 EUR, to make you miserable and suicidal in a span of just two weeks. Totally unethical, don’t you think ;)?
I hope that those few tips will help you understand wtf they really want and gain a peace of mind, sleep better. The tips might sometimes sound ridiculous when you compare them to those from the shop pages etc. and feel free to disregard them if they seem to crazy. But you know…
DISCLAIMER: As I don’t (yet) have a Calathea white fusion, the course of action that I propose might not apply to them. I’ve heard that they are demanding players. If I do get one, I will totally write a separate article about that particular plant.
DISCLAIMER II: I do realise that Calatheas are Goeppertias in the new classification system, but I just want people to find my article more easily in the internet ocean. We all know them as Calatheas anyway.
Because Calatheas come from Brazil, Guyana and Colombia, it is common to think that they will feel good frying in the sun. The truth is, Calatheas prefer diffused light coming from North-East facing windows with rays caressing their leaves in the late afternoon – just like ferns. You will recognise excessive light exposure from fading colours and sometimes – yellowing in the middle of the leaves.
You probably have heard Calatheas being referred to as “prayer plants”, same as Marantas and Ctenanthe. They change the position of their leaves, and it looks like they are dancing or praying to the sun. The truth is, they do that even in a dark room with no sun, which is why I’m not entirely sure if those are nyctinastic movements at all. Such movements are associated with diurnal light and temperature changes and controlled by the circadian clock and the light receptor phytochrome.
Probably the most important care component for Calatheas is watering, as they are very sensitive to changes in pH and temperature in their root system. How to do it properly?
- WHEN: it is not about the time of the day, as they are not (or not supposed to be) in a very bright spot. It is about regularity. Pick your hour, pick the days and stick to the schedule. Calatheas like to be watered as often as it allows the soil to be damp at all times. For the first two weeks you will have to observe the new soil. How fast is it drying in the spot that you’ve put your Calathea? Then adjust the frequency of your watering. It will usually mean 2-3 times a week, with big Calatheas it can sometimes be lower: once a week, but it also depends on the season and the container (see more about this in the SOIL part, below).
- TYPE OF WATER: water should be soft, without calcium, because the optimal pH for those plants is 5,0-6,0 which is pretty acidic, and if the pH gets any higher – you will start encountering numerous problems with your Calatheas. I generally use rainwater or demineralised water for this genus.
- WATER TEMPERATURE: 25-30 degrees Celsius is optimal. Calathea roots are fine, sensitive and prone to root rot. Keep the water temperature constant and don’t give them the cold shower shocks, they will hate you and show it with the crispy, ugly foliage edges.
- HOW: water evenly all around the edge of the pot. Then the second time, and then remove the excess from the pot holder. Do not pour water randomly in one place (only part of the root system will get water, and the other part of the plant might die off) or splash in the middle of the plant. Water will stand in the leaf sheaths and your new leafs will be damaged right from the beginning.
Temperature & humidity
Do you mist your Calatheas daily and yet they have crispy edges? Well, that is probably why. First of all, is your misting water warm and mineral free? Probably not. Is your airflow in the apartament similar to the Brazilian breeze? Probably not. All you can do for those plants indoors is: gather them together so they are nice and cuddly, and put the humidifier close. Believe me, it is not only enough, but better than cold droplets sitting on the leaves. If your Calatheas are standing on the floor, it is better not to put them in a drafty place – extra protection for the sensitive roots.
Cuddle those roots
As I have mentioned before, calathea roots are more akin to capillaries than to big arteries with side veins. Therefore, they need more stable soil structure than eg. aroids do. Yet we do not want to strangle the roots. Again, reference to ferns comes in handy – we need loose soil, but fairly “packed”, so the roots can easily go trough and be well soaked. As always, I recommend to make your own mix:
- Palm mix 50%
- Fern mix 30%
- LECA for hydroponic 10% (not on the bottom, but blended in)
- Sand 10%
If you are not feeling confident with soil mixing – try just two ingredients : a soil mix for palms (that will bring the optimal pH) and a mix for ferns 1:1.
Do Calatheas like to be root bound? No, when the roots start to touch the pot they will probably get too cold and you will soon see it on the leaves. I repot my calatheas 2-3 times a year. If they grow properly, of course. Always choose a pot that is one size bigger, as pots which are too big can actually make Calathea grow slower. Too much “free” soil unoccupied by the roots, means more moist and a higher risk of “cold feet”.
Watch and grow
As the flowers are not really flattering, it is recommended to use low potassium fertiliser. I think that it is a major mistake, because potassium is not only responsible for the flowering, but also crucial in the plant metabolism – growth of the baby plant, its immune system and especially – assimilation of nitrogen. Lack of potassium in the soil will quickly show on the leaves in the form of crispy edges. Use a balanced fertiliser, and if you get the flowers, well…just snip them. Better to have flowers than pests.
You can propagate your Calathea easily by division. Don’t water her for 2-3 days, and then get out of the pot and divide. Put the babies in the fresh soil. Congrats! You’ve made it.
A lonely calathea leaf will not root in the water. You need a piece with a rhizome.
Spider mite SPA
If you have a pest problem with calathea it is probably due to the presence of spider-mites.
They can also get fungi if you keep the soil soaking wet and cold for a long time and the airflow in your room is not proper – either harsh winds or “a soup” of motionless, stale air.
I do recommend to shower your Calatheas once a month to get rid of dust and for pest prevention. Either let them dry in a dark bathroom or dry the leaves with a soft towel afterwards.
Remember, even if your Calathea has bugs all over, you can always cut her to “0”, and it will grow back. Don’t worry and don’t throw her away ;).