When we bring new plants back to our homes we want to do the best we can for them. After all, it’s another life to nurture and help grow, something like a stationary new addition to the family. So we dig a nice big hole, add lots of organic matter and a good helping of expensive fertilizer. We gently place the plant into the hole, firm the soil around it, water it well, and two weeks later we try to figure out why it has gone all yellow and lost half of its leaves. Unfortunately its demise was a result of good intentions.

You see, the best way to kill natives is to give them more fertiliser than they actually need. So it’s the fertiliser in the hole and the added organic matter that has most likely led to it’s demise. The good thing about natives is that they don’t ask for much. Good drainage, enough to drink and a layer of mulch is all that they need.

Another common cause of death for native plants is the practise of teasing out the roots. This may be fine for some European plants, but our natives will complain bitterly if you disturb their roots. After all, they have delicate, super-efficient roots which have evolved to extract nutrients effectively from our nutrient deficient Australian soils.

If you’re worried about buying a root-bound plant, there is a simple solution. Ask the nursery staff to show you its roots by removing the pot from the plant. And if you see a mass of roots wound around the inside of the pot, simply choose a younger plant. Speaking of removing pots from plants. Never grab plants and pull them out of their pots. Always remove the pot from the plant. If this makes no sense to you, come to Yuruga Nursery and get a staff member to demonstrate it.

Which brings me to the final point. No, you can not plant them while they are still in their pots! Some people have actually tried this method with, predictably, very unfavourable results. At first the plants will just sit there and grow very slowly as the roots try to make their way out of the pot via the drainage holes. But finally they will die, strangled by the tight plastic collar around their base. Unfortunately, I’m not kidding, I’ve seen this done before.

Planting natives is a simple activity and it’s best kept simple – just remember… green side up!

Marcus Achatz
Yuruga Nursery

(Published in Cairns City Life magazine, March 2009)

Lots of people like to build up their garden beds by adding extra soil. This is a very popular approach to gardening, particularly where your original soil is quite poor or if it is poorly drained.

However, there are serious traps for the unwary, so here’s our advice to you ..

Raw material suppliers often sell ‘manufactured’ garden soils, ie blended products made up of a mixture of various components eg sand, loam, compost etc,

Most of these products also contain added fertiliser so as to give your garden a boost.

The biggest problem with these soils is that the fertilisers added to them are designed to suit typical exotic gardens and so they invariably have a phosphorous level which is too high for native plants. It is very common to hear that natives planted in these soils either die or show severe stress and yellowing. So before you buy any garden soils, get a cast-iron guarantee that there is either no added fertiliser, or that any fertiliser added has a phosphorous level of 3% or less.

Many of these garden blends also have added lime or dolomite, to ‘sweeten’ the soil to suit typical exotic gardens. The trouble is that lime and dolomite are alkaline products which raise the pH of the soil, and natives need acid soils. So there is a very real danger that the soil you buy may have a pH which is too high for natives, in which case your natives will either die or do very poorly.

Another problem, of course, is the danger of buying more than you bargained for, and finding you also have serious weeds such as nut grass, or very serious fungal diseases such as the root-rot fungus Phytophthora.

Dumping extra soil on top of hard ground is not a substitute for preparation of your original soil, even though it may sound an attractive way of getting out of a bit of hard yakka. Even if you import additional soil, the soil surface must be loosened so that the roots of your plants will be able to penetrate into the original ground. If you don’t do this, there will be a hard interface between the two soil types, and when the roots hit the original ground they will either stop growing or grow along the interface horizontally. Either way, the plants will have poor roots systems and will be prone to blowing over.

Our advice to our customers is that, for native gardens, there are lots of risks in buying-in extra soil, and in many cases there is really no need. For more information about this subject, see our Yuruga Information Sheet “Soil Preparation“.

The focus of this article is for gardeners in tropical Australia.
However, the basic principles apply for throughout Australia
with minor modifications for local conditions.

Creating a rainforest garden is easy!

There are two secrets to creating a rainforest garden, and no, they are not water, and more water! In fact, water is no more a necessity for a rainforest garden than it is for any other type of garden.

The two secrets are:

1. Dig up the garden bed thoroughly to provide as much loose soil as possible;
2. Provide a thick layer of organic mulch.

Soil Preparation

Rainforest plants, as a general rule, have very timid root systems. Unlike acacias, eucalypts and grevilleas which have robust root systems capable of penetrating hard ground, rainforest plants have timid, shy root systems that tend to stop dead at the first sign of an obstacle. Consequently, rainforest plants planted in hard ground simply will not grow.

Rainforest plants grow best when you garden in the traditional fashion – pretend they’re roses or a vegetable garden, and plant them in a bed of thoroughly loosened soil. The ideal depth is about a foot (30cm). On a small block of land, this means rolling up your sleeves and getting stuck into the ground with the pick, shovel and elbow grease to physically break up the soil. You haven’t finished until your original hard lumpy ground is nice and soft and friable.

If you are planting a large garden, it’s well worthwhile to use a machine – a bobcat or backhoe, or even a small bulldozer with rippers can prepare a large garden bed in a flash. It’s not expensive – for less than one hundred dollars you can prepare a garden bed which would take many days to prepare by hand, and the resulting plant growth will be spectacular to say the least. (See Information Sheet ‘Soil Preparation’)

Mulch

Mulch is absolutely essential to grow rainforest plants well. The mulch should be organic and applied as a thick insulating layer on top of the soil much like a blanket covering a bed.

Thick organic mulch is essential for several reason, including:

• It keeps the soil moist by reducing evaporation
• It controls weed growth
• It keeps the soil cool
• It provides a source of recycled nutrients
• It keeps the soil healthy by maintaining a balanced population of micro-organisms

Unlike most acacias, eucalypts and grevilleas, rainforest plants are very surface rooted. It is therefore essential to keep the surface of the soil cool and moist, otherwise the roots will bake and dry out.

As we said above, rainforest plants have timid roots; give them an obstacle and they give up very easily. If you allow weeds or grass to grow around the base of rainforest plants, they cannot compete.

Weeds and grass will severely inhibit the growth of rainforest plants. A thick application of mulch will keep weeds and grass at bay.

For rainforest plants, it is essential that the mulch be organic, since the recycling of nutrients is very important for their growth.
The type of mulch you choose is not important, so long as it is organic. You can use anything, so long as it was once a plant. In north Queensland, bales of mulching hay are popular. In some areas, peanut shell may be available. Many shire councils sell mulched-up garden waste. Wood chip is fine. Newspapers and cardboard are OK, but it is best to shred them first – if you spread them out in sheets they act as a thatched roof and prevent water penetrating the soil beneath. (See Information Sheet ‘Mulching Your Native Plants’).

Mulch should be applied as a clean blanket on top of the soil surface. It should never be dug into the soil – this is for compost, not mulch.

Things such as black plastic are no substitute for organic mulch. Black plastic does not allow the soil to breathe, and it does not allow the recycling of nutrients that is so important. In warm climates, it can cause the soil to overheat. Don’t use black plastic. If you really think you need to, don’t. Make your layer of organic mulch twice as thick instead.

Watering/humidity

Provided you have a thick layer of organic mulch, you will find that you don’t need to water your rainforest garden any more than a normal garden, although it will love any extra water you can give it. Of course, your rainforest plants must be watered for the first few months until they are established, just like any plant, be it a wattle, grevillea or callistemon. (See Information Sheet ‘Watering Your Native Plants’).

However, rainforest plants as a rule cannot tolerate dry winds. Unlike acacias and eucalypts etc., which have a thick waxy cuticle over their leaves (among other adaptations) to prevent excessive moisture loss in dry times, rainforest plants have little protection against evaporation since they have had no need for it in their natural habitat. It is more important to maintain a reasonable humidity level in the air than it is to apply water to the roots.

To grow some of the more delicate species in drier areas such as Townsville or Mt Garnet, you may need to trap humidity around your plants by planting a shelter belt of hardier species or by creating a courtyard.

Fertiliser

Rainforest plants love to be fertilised – fertiliser brings out the lovely foliage colours that make rainforest plants such a delight to grow.

The rules for fertilising rainforest plants are the same as for ordinary natives – check the N:P:K ratio to make sure the phosphorus is low – less than 3% is best.

Water in well, and don’t overdo it. Like medicine, a little is good for you, an overdose can easily kill. (See Information Sheet ‘Fertilising Native Plants’).

A handy reference to rainforest plants for your garden:
‘Growing Australian Tropical Plants‘ by Radke & Sankowsky

Let’s dispel some of the common myths …

Myth : Rainforest plants need to be planted in the shade.

Wrong! Just because the rainforest is a shady place to walk in, does not mean that rainforest plants need shade. What it means is that rainforest plants cast shade. In fact, if you walk through the rainforest you will notice that the seedlings on the floor of the forest in the dense shade are not growing – they are sitting in a dormant state waiting for a gap to form in the canopy so that the sunlight can stream in. It is only when they receive full sunlight that they start growing.

If you plant your rainforest plants in the shade, they will grow slowly, and they will become thin and lanky as they struggle upwards to the light.

Rainforest plants can, and should, be planted in the full sun, where they will grow thick and bushy and flower young. In their natural habitat, most rainforest plants do not flower until their canopy is in the sun. By planting them in the full sun from the start, you will trick them into believing they are already at the top of the canopy.

Of course, this does not apply to the shade dwelling understorey shrubs of the rainforest – these naturally need the shade – so use your commonsense!

Myth : Rainforest plants are too large for ordinary gardens.

Wrong! Most rainforest plants grow in the garden to only about a quarter or a third of their height in the forest. By planting them in the full sun from the start, they have no need to grow taller and taller to reach the sunlight, since they think they are at the top of the canopy already. I wonder how many of you have an Ivory Curl (Buckinghamia celsissima) or Golden Penda (Xanthostemon chrysanthus) in your gardens? Would you have planted them if you had known that they are rainforest trees from north Queensland, where they commonly grow 20-30 metres tall in the forest? In cultivation, however, they are rounded shrubs of only about 5-8 metres, and this is true of most rainforest plants, with the exception of plants such as the Kauri Pine and Bunya Pine.

Myth : Rainforest plants should be planted under a canopy of existing trees.

Wrong! Plants planted close to existing trees generally do poorly due to root competition and lack of sunlight. Take the plunge, and plant your rainforest trees in the sun from the start. Most of our rainforest plants for sale are in the full sun in the nursery, so don’t be afraid to plant them in the sun in your garden.

Myth : Rare plants are difficult to grow.

Wrong! Some rare plants are quite hard to grow, but many are surprisingly tough and hardy. Rarity is often more related to habitat isolation, than to any intrinsic feature of the plant itself.

Myth : Rainforest plants can only be grown in soil that matches the soil type in the wild.

Wrong! Rainforest plants can be grown in almost any type of soil. Mulch and loose soil are the main requirements; fertilise if necessary.

Planning your rainforest garden

To create an attractive rainforest garden that is pleasing to the eye, you need to use a fair proportion of hardy, bushy species that will give the garden its basic structure, bulk and backbone. There are many species that fit this bill, but some examples are the hardier, tougher Syzygiums and Acmenas, and plants like Flacourtia, Scolopia and Xanthostemon.
Pay special attention to the plants that you place on the edge – these are the ones that hit you in the eye every time you look at your garden. On the edge, you should place the plants that have an attractive shape, attractive foliage or spectacular flowers and the plants that could be smothered if placed in the middle of the garden.

Leggy plants are best in the middle.

Your garden should include where possible plants for birds and butterflies, flowers and fruits. The Yuruga Information Sheets ‘Attracting Birds’ and ‘Attracting Butterflies’ give you more information.

Having taken this approach, then you can start placing the more unusual plants that have specific requirements in and amongst this basic backbone.

Happy Gardening!