Soil

A standard aroid potting mix that’s moist, well draining and rich in organic matter is what the philodendron painted lady wants. This typically includes a mix of coco coir, worm castings, orchid bark, perlite, activated charcoal and pumice, though you can leave pumice out of the mix if your plant is in its juvenile stages. 

I use this mix and have seen good results:

• 40% coco coir (instead of soil)

• 20% orchid bark

• 10% perlite

• 10% worm castings

• 10% pumice

• 10% activated charcoal

Light

You’ve probably been told that your philodendrons will only thrive in bright, indirect light, nothing more. To some extent, that’s correct. Your philodendron painted lady will thrive in lots of bright, indirect light, BUT you’ll see richer, bolder colors and larger leaves if placed somewhere that also gets 1-3 hours of direct cool morning or evening sun.

Problems with scorching and bleaching only crop up when a plant is left in direct light for hours on end, especially during the afternoon when light is more intense. Solely bright, indirect light is not a hard and fast rule.

Watering

Like most philos, the philodendron painted lady loves evenly moist soil that’s never too dry, nor too wet. The key to mastering ‘watering’ is to get into the habit of checking when your plant really needs water as opposed to relying on a strict ‘once a week’ schedule like many guides tell you to do. 

Humidity

As a result of being crossed with two tropical plants, this plant loves humidity. The higher the better. Anything more than 70%+ will result in larger leaves with brighter coloring. Lower humidity levels 40-50% will cause smaller leaves, but you won’t see hugely drastic changes to its appearance. Friendly reminder that humidity is nowhere near as important as getting light, water and fertilizer right, so try not to worry too much.

Fertilizer

Houseplants have no natural way of obtaining nutrients once they’ve absorbed the nutrients in their potting mix or soil. It’s why they need regular fertilizing. If you’re using coco coir, you’ll definitely need a good quality fertilizer as it doesn’t contain any nutrients your plant can actively use.