When it comes to watering your house plants, there are so many factors that can affect how often you need to water your plants and there really is no straight forward "water once a week" answer (unfortunately!) The best way to learn when to water is to watch and observe your plants, take note of your environment and do some research on your plants about where they originate from. This will give you a better understanding of what their different watering requirements may.
Here are a few things you need to consider.
Where does the plant originate from?
How much light does your plant get in your home?
What temperatures are your plants in?
What substrate do you have the plant in?
How often do you WANT to water?
Knowing these few things will really help you gauge an idea on how frequently you should be watering your plants. Let's dive into each question a little more and why it is important to know.
Where does the plant originate from?
Knowing where your "house plant" originates from will give you a great idea on the conditions it prefers and needs to thrive. Now I understand our homes are not moist, humid tropical rainforests like many of our "indoor plants" prefer, but you can mimic some of the conditions to keep your plant happy, and this also gives you an indication on what their water requirements may be. On the flip side, if your plant is a cactus for example, and comes from hot, dry, arid conditions then you know that its need for watering will be a little less frequent.
How much light will your plant get in your home?
How much light your plant receives will affect how quickly your plant grows and how quickly water will transpire through the leaves. The more light your plant receives, the quicker it will use up the water, therefore may need more frequent watering. Alternatively if your plant is in a lower light position, it may grow slower, meaning it doesn't use the water up as quickly, therefore will need watering less frequently.
What temperatures are your plants in?
This kind of goes hand in hand with the previous question. Once again, the warmer the environment a plant is in, the quicker it will use up water and when temperatures are higher, water will also evaporate from the soil. The cooler the environment, the slower your plant will use up water, meaning your soil will remain moist for longer periods.
What substrate do you have the plant in?
This will once again will determine how often you'll need to water. For substrates like Pon or Leca, they will only need watering (and by watering I mean topping up or refilling their water reservoir) once every 2-4 weeks. A substrate like our Wildvine Hoya & Aroid Blend will dry out quicker between waterings as it is a soil-free, chunky and aerated blend, where as our Wildvine Premium House Plant Blend will retain moisture longer due to it being a soil based blend. If you were to use a potting mix straight from the bag from somewhere like a garden centre, where they are denser in texture, then these will retain more water for longer (but is not always a good thing! Especially in cold seasons. Wet & cold = Root rot)
5. How often do you WANT to water?
Again, this goes hand in hand with the previous question. If you are a plant parent that loves watering your plants often (bit like myself) then a chunky, free draining, airy mix will be your best choice. If you tend to under water, then maybe try a soil-based mix, which will retain a little moisture (but still with added drainage like perlite, pumice or orchid bark) because plants need aeration and oxygen around the root zone.
If you are a serial forgetter or you go away for short periods often, then growing in a semi-hydro setup, like Pon or Leca will be a fantastic option, as they are sitting in a water reservoir and as long as that is full, they'll be happy!
Now you have figured out your growing environment, what type of waterer you are or want to be and what your plants needs may be, here are a few things that can help you learn when your plant needs water using visual cues.
First off, is "the best thing since sliced bread" in the plant world and that is clear pots!
They are hands down the best way to help determine if your plant needs water or not. Being able to see the substrate and root system visually will help you learn how long it takes for the substrate to dry out and what colour the substrate is when dry vs freshly watered. As per question number one, if your plant comes from a tropical environment, it may like to dry out to around 50%, so if you look at your plant in its clear pot and you see the substrate is dry to about half way down, then that's a good visual cue your plant may need water. Or if your particular plant likes to dry out completely before watering, being able to see through the clear pot will take all the guess work out of it!
Clear Pots - Amazon - If you're not in NZ then these pots are great! I have tried them before and rate them.
Another great watering tip is to become besties with your plants, get know them inside and out. Taking mental notes of how your plant looks visually when it is adequately hydrated vs when it is dehydrated. Some plants give you subtle clues they're thirsty and some.. not so subtle (I'm looking at you drama queen Peace Lily!)
For example, some things to look out for when your plant may need a good drink is pale leaf colouring, drooping petioles & stems, curled leaves and soft or wrinkly leaves (especially on plants like Hoya). In extreme drought cases (too long between waterings) you may experience yellowing leaves or leaf drop. Below are some examples of what to keep an eye out for..
The Philodendron micans leaf on the right is what a hydrated leaf looks like, the Philodendron micans leaf in the middle is showing that it is dehydrated, as it is curling in at the sides, and the last image is of a Monstera adansonii which is extremely thirsty, it's pale in colour and its leaves and petioles are drooping and floppy.
Left - Monstera dubia ~ You can see its leaves are curling around the wood, when the plant is well hydrated they lay flat. This is a good indication this plant needs a water.
Right is a peace lily being the dramatic queen she is. I went too long in between waterings so its lowest leaf yellowed. A good indication that this plant may like to be kept a little more consistently moist.
Left is a Hoya multiflora leaf, these leaves are usually quite smooth and slightly firm when well hydrated, as you can see by this image the leaf has some wrinkling and veining showing and is dull in colour, meaning it is due for a water.
These are just some examples of what to look out for in plants when they may require watering. Learning these cues can dramatically help with avoiding overwatering and under-watering issues. As I mentioned at the start, unfortunately there isn't a "water once a week" answer for the ever burning question of "when do I water my plants?".
There are a lot of factors that play a part in the frequency of which you need to water but I hope these tips can help shed some light on what to look out for in your plants.
There are watering gizmos and gadgets you can get, but I personally feel they are a little bit of a waste of time. The two simple methods of clear pots & knowing your plants thirsty cues will be the best way for you to learn when plants need water, it really doesn't have to be over complicated.
I hope this is helpful for you, if you have any questions, please feel free to leave a comment and I will get back to you :)
-Kate x
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