Larry Smith and the Riverside Gardens team talk all things pots, plants and pruning in their weekly gardening column.
After being asked to give a talk at Tatura Garden Club this week on indoor plants, I realised I had not touched on this topic in this column. So, you guessed it — this week we will have a quick look at indoor plants.
Since the first COVID-19 lockdown, indoor plants have enjoyed a resurgence in popularity. This time around, people are looking for a far more diverse range of plants to use, and whether wise or unwise, they are being a lot more adventurous in their plant selection.
Our garden centre’s ‘indoor plant COVID project’ was about constructing an indoor green-walled garden on the south wall of our shop, which is now 8m high, with foliage cascading all the way down. It also incorporates 10 fern baskets hanging from the roof with fronds more than 2m long. It really has changed the atmosphere and feel of our shop and is a good example of what can be achieved by bringing living foliage inside.
Indoor plants not only beautify indoor spaces, but they also have other health benefits. They have been proven to help relieve stress and noise, boost creativity and productivity and promote recovery. There is also evidence that indoor plants may positively influence air quality in your home or office.
The majority of plants that we grow as indoor plants are understorey plants from tropical or subtropical rainforests that enjoy humid, warm conditions and filtered light. These are the conditions that we should try to imitate to grow them inside successfully.
The main question we get when customers purchase indoor plants is, “How do we know when to water them?”
The easiest solution is that if the potting mix feels moist to your finger, then it does not need watering. I feel more indoor plants are killed with kindness rather than neglect, either by overwatering, over-fertilising or placing them outside for extra sunshine.
As a rule of thumb, most plants grown inside will require watering only about once a week, and if grown in a water-well pot or on a wicking system set-up, this could be as little as once every two to three weeks. These systems are easy to set up, so if you would like to give it a try, call in and chat with us, and we can give you a quick run-through.
A good-quality potting mix is essential when re-potting indoor plants; it needs to be free-draining and formulated for indoor use. The plants are growing in a warm, humid environment, and poorer-quality mixes can cause a range of problems that thrive in this environment.
Indoor plants require regular fertilising because they are potted plants. In addition to being uptaken by the plants, nutrients can be leached out of the potting mix each time we water.
In the office, we mainly use Searles’ ‘Green and Growth’ liquid fertiliser or Osmocote pots, planters and indoor slow-release fertiliser. Neither of these are organic products, so there is little chance of a smell being associated with them through the office space, and we get excellent results. That’s not to say that organic products such as Maxicrop for indoor plants can’t also give great results.
Even though your plants are indoors, pests and diseases are still going to make their way on to them. These problems are best treated on an individual basis; we are always here to help identify and suggest treatments for each problem as it arises. Also, being in an indoor environment, you do need to be mindful of the products you use, and there are a lot of organic or low-impact remedies that work extremely well.
A good example is the treatment of fungus gnats, which are tiny flying insects that can set up home in the potting mix of your indoor plants. These can be controlled quickly and effectively with small yellow sticky traps placed just above the surface of the potting mix. This is a lot easier than any soil drench treatment or spray treatment.
Well, I have gotten this far, and it just occurred to me that I still have not mentioned a single indoor plant variety or suggested what you could use for a particular spot. With such a range available, that might have to be a topic for another day.
Happy indoor gardening.