Late winter to early spring is the best time to start planting. Because of the cool weather, the plants will be largely dormant and will therefore be less likely to suffer transplant shock. It also gives the roots some time to get established before the hot weather hits.
That said, some species such as Lilly Pillys, Pittosporums, Casuarinas and Lomandras can successfully be planted from late summer right through to late spring.
Never plant species just before a forecast heat wave or windstorm.
Final Site Preparation
Once all the lantana and other weeds have been cleared from a site, there are just a few steps to properly prepare the site for planting.
Remove as many regrowing weeds as possible. This can be by manually pulling them out, spraying them or using a brush cutter.
Remove all fallen branches, stumps, rocks, twigs etc that might interfere with the plantings. The goal is to get the area as workable as possible.
Mark any naturally occuring native seedlings.
Measure out where the trees and other plants will go. This step is absolutely essential as it ensures that the trees will not be overcrowded as they mature. Because seedlings are so small, it is very easy to plant them too close together! Not only that, but better spacing means more area can be revegetated with the available seedlings.
Planting
Dig a hole at least twice the diameter and 1.5 times the depth of the pot. Bigger holes are better because they result in more loose soil around the plant. This improves water absorption as well as allowing the roots to grow more easily.
Mix a handful of saturated water crystals with the soil at the bottom of the hole. The water crystals hold significant quantities of moisture for the seedling to access through dry spells.
Place one fertiliser pellet in the bottom of the hole.
Plant the seedling so that the surface of the soil in the hole is at least 10cm below the surrounding ground level. This helps with watering and water retention because it prevents the water running away. It is still very important though to ensure that the seedling’s root ball is completely covered with soil.
Water in the seedling to settle the soil and reduce transplant shock.
Stopping Intruders
Almost all new plantings must be caged or the wombats, roos and deer will have a nice little snack. We have experimented with various forms of fencing and cages. The most effective method appears to be to individually cage each tree with 1.5m high 25mm x 25mm square wire mesh supported by three star pickets. Larger mesh such as dog wire doesn’t stop roos putting their heads through and having a snack. Similarly, anything less than 1.5m high allows deer to lean over the top and eat off the new growth.
We typically make the cage diameter no less than 1m to allow tree to spread and leave a 15cm gap between the wire and the ground to allow easy access for weeding and watering and to prevent birds from getting trapped. Star pickets should be hammered in with the holes facing outwards as this makes it easier to attach the wire mesh. The pros and cons for each other form of caging are: (All the plants in the pictures below were planted at the same time and were roughly the same size. The extent of growth in each form or cage was consistent between species.)
Green plastic bags with bamboo stakes Pros:
Cheap
Easy to set up and reuse
Cons:
Are like ovens in summer
Too short to prevent most animals
Aren’t wide enough to allow tree to spread
Bamboo rots within one year
Black plastic mesh cages with hardwood stakes Pros:
Cheaper than star pickets and wire
Easy to set up and reuse
Do not cook the trees in the same way as green plastic bags
Cons:
Do not allow the trees to spread
Not usually high enough to stop the tops of the trees being eaten
Hardwood stakes rot within one to two years
Can be difficult to weed inside due to lack of room
120cm wire fence surrounding planting area Pros:
Prevent people walking into regeneration area
Marks a distinct boundary
Cons:
Wombats can get fenced in with disastrous results
Wombats dig under the fence or push through it
Roos and deer jump the fence
Costly to set up
Individually fencing each tree Pros:
Prevents deer and roos - they just seem to go around
Wombats don't knock the cage over
Easy to maintain - well defined maintenance area
Allows tree to move freely and therefore to strengthen
Cages are reusable
Cons:
Expensive
Slow to set up
Watering
New plants must be watered fairly often until they begin to get established. Depending on the weather, this can be as often as every two weeks for the first six months after being planted. The easiest way to check if plants need watering is to just scrape away some of the top soil near the plant. If it is slightly damp and clumps a little, it is probably ok. If it is dusty and looks dry, it’s time to do some watering. Do not wait until the plants start to look wilted or stressed. In particularly hot or dry conditions, we water all our plantings even if they have been in the ground for several years and look reasonably established. It would be very disappointing to watch a tree grow for several years only to have it die from lack of water! It would also leave a hole in amongst the other plantings which could take several more years to fill.
When we do water, we normally put at least two litres on each plant. Assuming a plants initial root area is about 25cm x 25cm, two litres equates to an equivalent of 32mm of rain. (1mm of rain = 1 litre per 1m2). To put that in perspective, average rainfall through the summer months is over 100mm per month so 32mm every two weeks is still substantially less.
Weeding
Tree cages must be weeded regularly both inside and outside. Weeds left to grow to near the young plants can smother them, take excess moisture and make them hard to spot when spraying weeds.
It is easiest and most effective to pull out weeds by grabbing the stem just above the ground. This ensures that all the roots come out with the rest of the weed and that the stem doesn’t just break off. When weeding inside a cage, identify the tree stem and simply pull out all the others stems under the wire or mesh.
Spraying
Glyphosate A new planting area will require spraying fairly often to prevent annual weeds taking over. However, some herbicides such as glyphosate should be used with some caution. Current scientific research is showing that too much glyphosate in too short a time can leave a residue in the soil which slows down the natural growth of the desired plants. Because plants don’t normally absorb glyphosate via their roots, the reason growth slows in poisoned soil is not yet known. All that is known is that it has a significant impact.
Nevertheless, glyphosate should be used for control of species such Turkey Rhubarb and any undesired grasses.
We follow a few research-based rules in relation to glyphosate use to minimise contamination risks.
Glyphosate's half-life is approximately 42 days but this varies according to the temperature and amount of rainfall. A site should therefore not be sprayed any more often than every 42 days (6 weeks).
Spraying should occur no more than four times a year on a site with sandy loams (two to three on clay soils). We generally don’t spray glyphosate on planting areas in winter so this rule effectively means we can safely spray every 6 weeks during the growing season.
Glyphosate takes much longer to decay in cool, dry weather than in hot, wet weather. Timing it a few days before rainfall will reduce the risk of build-up in the soil.
The glyphosate to water ratio MUST be kept to the amounts recommended on the bottle.
Phosphorous based fertilisers should be avoided altogether because the phosphorous binds with the glyphosate and thereby prevents its natural dissipation.
Weeds sprayed with glyphosate should be kept away from desired plants because glyphosate residue in the leaves of dead weeds is much slower to break down than residue in the soil.
Repeated spraying has resulted in some weeds evolving a resistance to glyphosate. Fleabane is a good example. Spraying should therefore be minimised lest we create more resistant species.
Dicamba/MCPA Dicamba is our preferred herbicide for controlling weed growth in planting areas. It kills all broadleaf weeds but has no impact whatsoever on grasses. This makes it ideal for allowing native or pasture grasses to return to a cleared site.
Safe chemical use guidelines should always be followed in relation to its use.
Metsulfuron Metsulfuron is also used as an alternative to glyphosate in regeneration areas due to its lower risk to grasses, though it will still weaken them. It is good for control of woody weed species that may come up in a planting area but are not affected by dicamba, eg tobacco, lantana, blackberry.
