Killing with kindness? Or perhaps forgetfulness... we're all guilty of improper watering sometimes, but with a little knowledge and a few tricks, bad watering habits can be a thing of the past!!
Accurate watering comes with experience, I cannot emphasise this enough!! It's a skill and you will make mistakes from time to time. Keep in mind the care instructions that come with a new plant are just guidelines and how often you need to water will greatly depend on the positioning of the plant & the temperature in your home. It's always a good idea to do some additional research of your own, finding out the native country of a species and it's natural habitat gives a firm indication of the what it needs to thrive.
So when is the right time to water? As a general rule it's advised to wait until the top 2 inches of soil is dry before deciding if it's time to water, preferably in the mornings.
There's two tricks that will help you, both work exceptionally well and I use them both myself.
Feel if the soil is still moist, how deep you need to press your fingers into the soil will depend on the size of the pot, this could be anything from 1 - 3 inches, sometimes more depending on the soil type (Coconut coir can be deceiving and appear much drier than it actually is). I find this method is especially useful when checking large plants that cannot be moved easily.
Familiarise yourself with the weight of a pot before & after watering. A plant will feel considerably lighter when it needs water. I use this trick often with my smaller plants and know instantly if anything is thirsty!!
If you find a gap around the soil within a pot, then you'll need to water immediately as this indicates there is no moisture left at all. In this situation it's best to let the plant absorb water in it's own time, see the method 'watering from below'.
Choose your method!! The two basics are, from above & from below:
Watering from above requires precision to avoid getting the leaves wet, but it's my preferred method. Water around the edges of the pot, avoiding the base of the plant. Watering little & often this way is ideal for plants that like to stay moist, particularly Aroids. Until you are familiar with how much water is needed always allow any excess water to drain away and decrease the amount you give in the colder months.
Watering from below is highly recommended but not always practical. The idea being plants can absorb water for several hours, then allow any excess to drain away before putting back into position. Place single pots into saucers or together into a tray for efficiency. It will raise humidity and prevent nutrient loss but, you risk saturating the soil if left for too long. In the height of summer this will be less of a problem and it's the only time of year I'd personally use this method myself.
There's pros & cons to any method of watering so find one that suits you. As I said earlier, it's a skill that comes with practice and even the most experienced plant parents get it wrong sometimes!! But do I understand how disheartening it can be when you're really struggling getting your technique right. Have patience and use those tricks to check the moisture in the soil before you turn on the tap!!
If your problem is forgetting to water, then make yourself a weekly reminder!! Alternatively, try keeping species like Sansevieria, Zamioculcas zamiifolia, Ficus elastica or Aspidistra elatior. They are extremely forgiving and won't kiss you goodbye the moment they slip your mind.