Zenith Zoysia Seed to Develop a New Oval in the Tropics - Part 4 - Maturing the Grass

It always take some time to develop an oval to the stage where it is getting ready to use.

Plants need to thicken and develop a dense sward above the ground surface while also developing their roots so they can effectively resist all the pressures on the grass that occurs during the playing of ball games or anything else planned for the oval  - it has to mature.

There will need to be regular mowing at about a 7-10 day interval - even more frequent in some cases - to help thicken the sward as lateral growth is encouraged, to fill any thin or bare spots.  Fertiliser is applied - normally at about 4 week intervals [ that is about how long normal agricultural type fertiliser can supply nutrients, particularly nitrogen, although other types [ phosphorus, potassium, trace elements] may be available for longer] for about 12 weeks,

Weed control is vital during this phase, to ensure the favoured grass is encouraged and impediments to growth removed.  Disease management and control may also be an issue in some cases.

In the period from around 45 days through to around 95 days after sowing the Zenith Zoysia area had a second application of fertiliser at about 8 -9 weeks [ 56+ days from sowing] and will be due for another at 12 -14 weeks, except this time it will be a slow release fertiliser, better suited to ongoing turf growth and with an availability period of 12 -16 weeks, thus preventing rapid growth, yet continuing to provide adequate nutrition for the turf for many weeks.

Weed control was instituted with several applications of herbicide.  The earlier applied residual herbicide continued to provide annual grass and some broadleaved weed control, but was boosted with two applications of a product that gives excellent knock down, but not very much residual weed control of broad leaved weeds - Kamba -M, applied at around 70 days after sowing and more recently at approximately 95 days from sowing.  Ideally the latter one would have been sooner, but a 48 hour dry period after application is needed for best results - and it continued to rain every few days!  Makes that a bit tricky.  The second application seems to have been very effective.

However, there have been issues with grass weeds.  While some grass weeds can be controlled with selective herbicides, the real culprit has been Bothriochloa spp plants - a particularly hard to control grass weed, and with few options for herbicide use.  The area did have a lot of these plants initially and were controlled with glyphosate before seed sowing, but the residual seed in the ground has germinated around the same time as the zoysia seed and slowly developed into a problem that requires hand removal.  The dense turf as it develops will eventually prevent most, if not all, future germination from the residual seeds, as well as the seed in the ground dying.  But in the meantime seedlings of it have to go...........  Resorting to hand weeding is almost inevitable in fine turf development, but it is labour and time intensive.  And requires many revisits to the same area to ensure it is all gone, as you can often miss small plants.

By mowing at 7-10 day intervals the weedy grass has time to put up a seed head between mowing periods, allowing easy identification, yet if removed in that 6-10 day time frame it is short enough to prevent any more seed development as full flowering has not started.  A real problem also exists in that the same species is all around the outside of the oval, and could easily re reintroduced to the oval area through mowing, especially if careless mowing of the oval surrounds is carried out.  Not an easy situation to rectify.  Although low levels are present initially, good progress in eliminating the Bothriochloa spp on the oval is progressing okay, but may require a few more weeding / mowing cycles, and ongoing vigilance.

Before mowing - 90 days from sowing

Before mowing - 90 days from sowing

Before mowing - 90 days from sowing

Before mowing at 90 days from sowing

before mowing - 90 days from sowing

After broad leaved weed control 98 days from sowing

Very effective broad leaved weed control at 98 days from sowing

At 98 days - Bothriochloa spp - grass weed in dense Zenith zoysia turf - note emerged seed head 7 days after mowing

Zoysia Seed to Develop a New Sports Oval - Part 1 - Hydroseeding

Hydroseeding works very well when you have tough conditions.

A monsoonal burst of more than a week,  over 100mm of rain in less than 2 hours  initially, continued ongoing heavy rain during the week [ more than 250mm], relatively short sunny breaks and lots of heavy cloud..........

Yes, a small amount of washout, but very small areas affected.

And at nine days from sowing when seedlings first appeared ..........was .looking very promising.

A true minimal cultivation operation based around a spray with glyphosate [ Roundup], a quick respray to kill off a few small missed spots after 4 days, hydroseeding with fibre mulch and zoysia seed after 7 days, when all plants were dead.

The recommended option of a short period of irrigation several times each day during sunlight hours was used [3 x 10 mins each time] to keep the surface damp - raining or not, with a slightly longer period early each morning to ensure adequate moisture at the surface - both VERY critical.  This irrigation started once sown, and monsoonal conditions did not start for several days after sowing.  Conditions at sowing were very hot - days around 34-35C, nights at 27-29C.

By day nine it was establishing very well. Yes, a few legume weeds were emerging which can be hand weeded, but will most likely be spot sprayed in a week or so.

There will be more of the story to come in the next two months as it develops.

So far it is a very promising early establishment.

hydroseeding with seed, fertiliser  and mulch 

Completed hydroseeding of oval - green from fibre mulch

seedlings at 11 days from sowing

yes - a few weeds too among seedlings  at 11 days

A bit of washout but still plenty of seedlings - at 11 days

general view at 11 days from seeding -- plenty of seedlings emerged - sun needed to boost growth

Uptake in Seed Use for Zoysia Turf Development - Need to Manage Weeds in Established Areas Not Just Mow

Both Compadre and its close cousin Zenith varieties  have seen a significant expansion of usage in domestic turf areas this Australian warm season, with Zenith sometimes being used because of tight seed supply for Compadre, still seen as the preferred variety.

While northern Australia continues with increasing use domestically, there has been some commercial use including where zoysia [ often Compadre as first choice] has been mandated as part of the commercial specifications.

As well, expansion has continued with Compadre especially being now very widely used as sod in commercial developments and areas of sod production have also increased, with Compadre now commonly the specified turf sod of first choice around much of north Australia.

The lateral growth [ rather than increased vertical growth], stolon density and potentially reduced mowing and maintenance plus overall good aesthetic appearance all contribute to this acceptance commercially.

That said, commercial users also need to understand that mowing is now not the absolute only maintenance required.

With many mowing contractors operating across many types of turf, vigilance and control to prevent entry of other turf species is needed [ often by adherence of seed and plant pieces on mowers], and specially to understand  that there are specific herbicide options to consider to keep the zoysia free of other turf species - with prompt maintenance a necessary practice to remove other, now weedy, turf types, to stop their spread.  Use of glyphosate [ Roundup(trademarked)] is not the only nor first option., although use of wick wiping with glyphosate to remove weedy grasses by killing via their seed heads may be an option for some species.......and yes it works well!  There are also very effective solutions for control of sedges in over watered or wetter areas of the turf area.

Mullumbimby sedge - serious sedge weed 

We can offer agronomic services to assist with weed control in zoysia, based on around 35 years of experience with the species in Australia, USA and Asia.

Where a considerable effort has been placed into higher quality turf, then it is important to also devote some effort and money to manage the areas more effectively for long term performance.  Do not ignore the turf weeds!!