1. Too much water, or not enough
Read the signs
When your plant is thirsty, the leaves wilt, leaf growth slows, lower leaves curl, lose colour or fall prematurely, leaf edges turn brown and dry, and flowers fade and fall.
When your plant is drowning, the leaves develop soft, rotten patches, leaf growth slows, leaf tips turn brown, lower leaves curl or yellow, flowers start to rot, young and old leaves fall at the same time and roots start to rot.
Before you water, poke a finger a few centimetres into the potting mix. If it’s dry, it needs water. But by following the saying ‘water little and often’ can simply fill air cavities in the mix, which not only denies the roots of vital oxygen, but also prevents water getting to the roots themselves, which is where it belongs. Many plants need to dry out before their next watering, and a big, long drink - even a soak in your bath or laundry tub - means water gets to the roots.
Read up about your individual plant’s water needs. Some, such as succulents, need less water than others. Others, such as pitcher plants that grow in water gardens, need a lot more.
2. Too much light, or not enough
Read the signs
If your plant is not getting enough light it will start leaning towards a source, such as a window. New growth will be paler and smaller than it should be. If it’s supposed to flower, it may not. It may just suddenly collapse because, without adequate light, your roots still stay soggy then rot.
If it is getting too much light, it will wilt, the foliage will curl downwards, and growth will become distorted. If it’s in direct sunlight too long, the leaves and stem will become sunburnt, removing protection to the inner workings of the plant.
Determine if your plant is light tolerant or not. Many indoor plants are understory plants from tropical or semi-tropical areas and, while they like the warmth of indoors, they prefer only dappled light. Fortunately most indoor plants are much easier to move than garden bed plants. Sit them in a tall plant stand so that you can more easily move and position them in different spots of the room.
Every room in your home has different natural light. Before positioning your plants, consider the aspect of your doors and windows. North-facing openings get all-day sun, south-facing may get very little light all year round, east-facing gets gentle morning light and west-facing gets harsh afternoon sun. Be prepared to move your plants as the seasons change and the sun rises higher and lower through the year.
3. Potting mix needs replacing
Read the signs
Your flourishing plants suddenly look tired and droopy, and seem too big for their homes. And when you try to push a finger into the mix to determine if it needs water, it’s solid.
Whatever nutrients had been in your potting medium have been exhausted. At the same time the roots have kept growing and are now probably too big for their pot. Remove the plant from its pot, trim off older leaves with clean secateurs, shake away remaining potting mix from roots and give them a trim. Consider getting a larger pot as the roots below and foliage above will continue to grow in a nutrient-rich new home. Replace with quality potting mix and feed with a seaweed solution to give the roots a tonic.
Add vermiculite and/or perlite to the mix. Both aerate the mix and hold water longer, although vermiculite more so. Perlite adds to the humidity around your plants, which many indoor plants need.
4. Dirt in the wrong places
Read the signs
Your leaves lack lustre, there are the fine webs of tiny spider mites and your plants’ growth has slowed.
Anything that covers leaves slows down photosynthesis, which is how plants convert sunlight into energy for them to thrive. Water a sponge or paper towel to wipe your leaves as part of your regular house-cleaning regime. Wash out sponges or use clean paper towels between plants so you don’t transfer dust and dirt from one plant to another. Or water and clean your plants by putting them under a cool shower.
Don’t use products such as cooking or furniture oil to make your leaves shine. They block the leaves’ pores – stomata - that release excess moisture and keep the air around the plant humid. These products also attract pests.
5. The heat is on, then off
Read the signs
Your foliage is fading, leaves are wilting, drying, yellowing or browning on the edges, and the potting mix is always dry.
Indoor heating dries out the air in your rooms, removing moisture essential to many indoor plants. If you’re at work all day and suddenly heat up your rooms when you come home, your plants will be regularly shocked and won’t cope if they’re in the direct line of hot air.
Air conditioning removes humidity as well, but also creates drafts that traumatise plants if these blasts are a daily thing.
Move plants so they’re out of the line of hot or cool air blasts. They’ll enjoy the ambience rather than a direct hit. Spray moisture around the plant regularly, even daily if your indoor temperature control is automated.
Tip Don’t put plants near open doors or windows exposed to cool or hot external winds. No one likes these drafts, and plants don’t either. Avoid putting plants next to windows exposed to the western sun. Glass radiates heat even in winter. Protect your plant with a sheer curtain or glaze your windows.
TIP! Look out for fungus gnats
These tiny flies hover over the surface of a pot and generally do no harm. The gnats are more annoying than anything else, but it’s an indication that you’re overwatering your plant. The gnats lay eggs in the mix and the hatching larvae feed on dead or decaying matter, usually rotting roots or the roots of seedlings. Treat by dunking the pot when the mix is dry in suitably diluted insecticide.
For more gardening stories, pick up a copy of the latest issue of Better Homes and Gardens magazine in selected newsagents and supermarkets or buy online today!
You might also like: