Caring for Indoor Plants

Even the most temperamental plants can be happy indoors, if you can give them the conditions they need. Because you have some control over your indoor environment, it's quite possible to make it a healthy haven for the plants you like best.

Here are the top 5 environmental variables to consider, to give an indoor plant everything it requires. Take your indoor plants from 'surviving' to thriving!

And if all else fails, there are a few sturdy heroes that will tolerate dimly lit rooms and barely any water – here’s looking at you, ZZ plant and sansevieria.

1. Light

Light powers plants! Photosynthesis is the process plants use to convert sunlight into energy - sunlight is critically important to plant growth.

As a rule of thumb, position indoor plants in a well-lit spot, but out of direct sunlight. A good example is just in front of a window with a sheer curtain. Being blasted with direct, hot afternoon sunlight is too much of a good thing - your plants will suffer. 

At the other extreme, shorter daylight hours in winter can mean your plants aren’t getting enough light to stay healthy until spring arrives. The simplest solution is to move all your plants to a sunnier spot, for the winter. 

Different plant species have different light requirements. Some are able to tolerate low-light rooms, so always check plant labels for their light preferences.

2. Air + Temperature + Humidity

These factors are really important for indoor plants. The reason we've bundled air, temperature and humidity together, is because they interact with each other - air temperature has a direct effect on humidity.

Air contains oxygen, which plants need for respiration (the process they use to release energy from stored sugars). Air also contains CO₂, which plants use for photosynthesis during daylight hours. Respiration and photosynthesis are both influenced by temperature - the processes slow down as the air cools, but as the temperature warms up, the plant works harder.

Importantly, air also contains water. This is where humidity comes into the picture. Humidity measures the amount of water present in air. The temperature of the air in a room dictates how much moisture the air can contain: warm air can hold more water vapor than cool air. When the air cools down, its capacity to hold moisture decreases. When it cools to the point where it runs out of space, the excess moisture condenses into liquid water. This is why you'll see condensation on the windows, on a cold morning.

Plants use the water in their pots for transpiration (where liquid water in the soil moves upward through the plant from the roots, evaporating through leaves as vapour, to cool the plant and circulate nutrients). Plants naturally release an enormous amount of water vapour into the air, which explains why the water in their pots disappears so quickly!

Humidity has a big effect on houseplants. When temperature is high but humidity is low, it's very comfortable for humans...but it makes plants transpire faster, which means they dry out faster. Because many indoor favourites have a high-humidity tropical origin, a warm, dry room isn't ideal to keep them happy!

Most types of indoor heating will dry out your home. Indoor environments can be much drier than plants prefer; even more so when you have the heater on during winter. For plants that originate in humid, tropical climates, like ferns and philodendrons, it’s good to spritz their leaves regularly with water. Placing a small humidifier near these plants will really help them. You can also group potted plants close together, to create a micro-climate that helps maintain humidity.

3. Water

Most plants can't survive solely on the water vapour in air, they also need to be watered, so they can transpire. Two of the biggest culprits for indoor plant death are underwatering and overwatering. Confusingly, the symptoms can look the same for both problems; they can both cause wilting and yellowing of leaves. Overwatering can also encourage root rot. In either case, prolonged dryness or saturated roots can be fatal to plants.

The good news is, you don’t need any fancy gadgets to tell you when it's time to water – just poke your index finger into the potting mix, down to the second knuckle . If it’s dry, water...but if it’s moist, you can leave watering for a few days. As a general rule, water once every week (until water runs out of the drainage holes), but extend this to every 10 days or so during the cooler months.

There's no one rule when it comes to watering indoor plants; different plants require different levels of moisture. The plant tag should provide some information on whether it needs consistent moisture (for example, maidenhair ferns) or prefers to dry out in between waterings (like ZZ plants or sansevieria). Alternatively, consult our Yates Plant Guides for help on an extensive range of indoor plants, cacti and succulents.

4. Potting Mix

Depending on the size of the plant you purchase, you may not need to repot it straight away. After a couple of months (or when the plant begins to outgrow its container), it'll be time to repot. Yates Indoor Plants Potting Mix is our go-to for most indoor plants. This mix contains a balanced fertiliser which gradually releases soluble plant food for up to 12 months, along with trace elements and seaweed to encourage root growth.

However, if you have cacti or succulents, they'll benefit from a specially-formulated mix, like Yates Thrive Cacti & Succulent Potting Mix. The recipe contains generous proportions of pumice, bark and organic matter to make it 'sharper' (free draining), because these plants really don't like wet feet.

Orchids also need a separate approach. Because most orchid species naturally live as epiphytes up high in trees, they've adapted to moist but very free-draining environments, so they have roots that catch and hold water. If the roots of potted orchids stay constantly saturated, they're at risk of rotting, so good bark-based orchid mixes like Yates Thrive Orchid Potting Mix are coarse and chunky, to encourage drainage and aeration to the roots.

5. Food

During the warmer months, when plants are actively growing, feed them regularly by adding Yates Thrive Indoor Liquid Plant Food to their water. This easy-to-apply product is fantastic for providing plants with the exactly right amount of nutrients to support healthy growth. It also helps green up any lacklustre leaves.

In winter, “less is more”. Plant metabolism naturally slows down over winter and a lot of plants go dormant as part of their growth cycle. They simply don’t need as much feeding; some types will be perfectly happy to fast for the whole cold season.

Some tropicals and trailing plants will stay awake during winter, so if you do want to feed you can use Yates Thrive Indoor Liquid Plant Food, diluted at the lowest ‘sensitive plant’ rate.

For feeding orchids, Yates Thrive Orchid Liquid Plant Food is a complete fertiliser that provides all types of orchids with the balanced nutrition they need. It includes potassium to encourage beautiful blooms, plus manganese, iron and copper; all ideal for your pot grown orchids.

Succulents and cacti prefer a slightly different diet; Yates Thrive Plant Food Spikes for Cacti & Succulents are a great solution. These fertiliser spikes are a concentrated source of nutrients that will feed indoor plants for up to two months. They're super easy to use – just push a spike into the potting mix mid-way between the pot wall and the plant stem.

If you like the idea of plant food spikes for convenience, our most popular version for general use is Yates Thrive Plant Food Spikes for Plants & Ferns.

Common Problems

Indoor plants aren't usually bothered by too many insect pests. Sometimes though, you'll find sap-sucking insects like mealybug, thrips, scale or mites on the foliage. The easiest way to control them by thoroughly spraying with Yates Natures Way Organic Citrus, Vegie Ornamental Spray. Always read the label first, to check the precautions for sensitive plants and hot temperatures.

Fungus gnats probably win the prize for the most irritating indoor pest. You can tackle fungus gnats with Yates Gnat Barrier, which forms an attractive physical barrier over the surface of your potting soil.

Common diseases of indoor plants include powdery mildew and leaf spots. Individual affected leaves can be removed and thrown in the bin. If multiple leaves are affected, spray with Yates Rose Gun or Yates Liquid Copper Fungicide (check the labels to double-check the diseases they control).

Good grooming is important to help keep diseases from getting started – strip off any dead or dying leaves or flowers straight away and discard them.

Handy Tips

• Mist spray plant foliage a few times a week.
• You can fill a plastic drip tray with large pebbles, part-fill with water and sit your plant on top of the pebbles to increase humidity around the plant.
• If your plants are looking a bit sad, give them a boost by putting them next to the shower while you’re in it, or in it after you've jumped out.
• It’s a good move to shift your tropical plants into your bathroom for winter. If you get a bit of condensation in the bathroom, it’s ideal! Another spot worth considering is right beside the kitchen sink.
• Keep plants away from draughts - you don't need to worry about air circulation for your plants; if there's enough for you to breathe, they'll be perfectly happy.
• Windows can radiate cold on frosty nights, so move your plants away from the glass. If you can close curtains or blinds behind them it helps insulate them.
• If you have shiny-leafed plants, you can protect and add attractive gloss to their foliage with Yates Leaf Shine...the lustre will last for weeks.