Picking the right time to buy matters in any market. Housing, shares, gold: the price of each moves due to a variety of global market forces, none of which have anything to do with when the buyer happens to need it. Grain covers are no different. A multitude of factors along the supply chain influence what a cover costs, and most of them sit a long way upstream of the fabricator.
The grain cover supply chain
The chain runs roughly like this:
- Crude oil and natural gas are refined into naphtha and LPG.
- Those feedstocks are ‘cracked’, mostly in Asia and the Middle East, to produce the polymers used in cover fabric: polypropylene, polyester for the scrim, and the ethylene used to make PVC.
- Resin is extruded into yarn or tape and woven into base cloth.
- The base cloth goes to a coating factory, often a separate business in a different location, where the coating is applied.
- The finished fabric is containerised and shipped to Australia.
- Jaylon cuts, welds and finishes the cover locally and delivers it to site.
Every step adds a variable: the oil price, plant outages, freight rates and shipping schedules. Almost all of it is priced in US dollars, so the exchange rate matters right up until the container lands. Only the last step is domestic, and fabrication is short, predictable and flexible on sizing in a way an imported finished cover is not.
None of the upstream steps follow the Australian harvest calendar, and in 2026 several have moved at once. The Strait of Hormuz has been closed to foreign shipping since 28 February 2026, when the conflict between Iran, the United States and Israel began. Due to its proximity to the epicentre of the polymer supply chain, the conflict has caused volatility in the cost and lead times of grain storage materials. That is the market grain handlers are buying into in 2026.
Why resin prices have risen
Gulf naphtha and LPG are the feedstocks for crackers across Asia and Middle East. When the Strait closed, those producers were short of feedstock, and the shortage flowed through to prices. Not only did the war prevent outbound vessels carrying crude oil, but it also prevented inbound vessels from supplying crude oil to ‘crackers’ within the Middle East. This situation created a disconnect between crude oil prices, for which alternative supply chains could be found, and polymer prices, for which there was insufficient alternative refining facilities. Force majeure declarations followed in both regions.
All three of the polymers used in grain covers have moved:
- Polypropylene sits around 30 per cent above pre-war levels, at a four-year high.
- PVC is around 25 per cent above pre-war levels, the smallest rise of the three, helped by a production base less dependent on Gulf feedstock.
- Polyester is 20 per cent above pre-war levels, following its own feedstocks up as paraxylene and PTA costs climbed.
Source: PolymerTrack, weekly polymer price data, 6 January 2025–5 August 2026. Chart prepared by Jaylon. Accessed 5 August 2026.
Ocean freight costs have also risen
Drewry’s World Container Index reached US$4,639 per forty-foot container on 9 July, its highest since September 2024 and around 40 per cent above the same period last year. The OECD reports ocean freight sitting near 45 per cent above pre-conflict levels, and has cut its 2026 world trade growth forecast to 3.1 per cent from 5.0 per cent.
The effect is indirect, but it is not small. It reaches Australia through fuel costs and war-risk insurance premiums:
- Carriers added rate restorations and peak season surcharges to the China–Australia trade from 1 July.
- Schedule reliability was 64.7 per cent in May, the best result of the year, yet the average delay on late vessels lengthened to 5.52 days.
- Port congestion reached its highest level since 2022.
So both the cost of landing fabric and the certainty of when it arrives have worsened. That matters more for a seasonal product than for one held in stock year-round.
The case for ordering early
Landed fabric cost can shift a long way between the point a handler starts assessing storage needs and the point they place an order. Waiting until the need is confirmed does not avoid that movement. It just means paying whatever the market is on the day.
There are three reasons to commit ahead of confirmed demand.
1. Preparing early gives you time to choose when to buy. Preparing for harvest as early as possible allows you to take the time to watch the market, discuss input costs with the fabricator and buy when the timing looks right. Given the high value of grain covers, this can make for a substantial dollar value saving.
2. A buffer against lead times. Vessel schedules are slipping and ports are congested. Ordering early builds slack into the schedule, so a late sailing is absorbed rather than passed on to the grain handler.
3. A place in the fabrication queue. Australian fabrication capacity is finite. When a large harvest is widely forecast, handlers across the country call for covers at the same time and fabrication schedules fill. Those who wait can find lead times have moved against them.
Large fabricators have capacity to absorb as much of this as possible. Holding fabric stock, buying forward and honouring quoted prices through a volatile period are all things a good fabricator will do to help handlers meet their operational commitments. But sustained movement in resin and freight costs eventually reaches the price of the finished cover.
The 2026 cover market is not one to be met at the last minute. Input costs sit well above pre-war levels, lead times are less certain than they were, and fabrication capacity fills quickly once harvest approaches. The 2026 harvest picture is unusually finely balanced.
More from Jaylon: Grain Storage Solutions · our agriculture range. Questions this season? Get in touch