Visit to the Arium, Thorner Lane, Whinmoor LS14 3FB on 8th May 2018
21 Headingley Rotarians and guests had a fascinating guided tour of the Leeds City Council’s new plant growing facility with Manager Andrew Culloden and his assistant, Lee Cawood. The name Arium is a protected brand with its own artwork used on labels, compost etc. Andrew took us to the rear of the vast (19,000 square metres) green-house which was purpose built on council land to replace the out-dated Redhall nurseries. We started at the point the plants leave the facility, either in vehicles for Leeds, or on trolleys for the shop. Council employees did the groundwork on this £6.5m build, which considering its size, went up remarkably quickly – it was started in January 2017 and they moved in during October. The buildings and fittings were purchased from Holland. The project was financed by the sale for development of the Redhall land not needed for the orbital road.
Adjacent to where we stood on a corridor big enough for fork-loft trucks, was a track along which plants could be easily moved. Behind which plants were growing in trays on waist high benches which could easily be moved utilising compressed air by one person who could clear one section in eleven minutes. This speed and ease of movement is key to large scale production. The plant trays were watered (with fertilisers added) from below, which encouraged good root systems and which meant the plants did not rot or scorch. Water collected from the roof and from condensation was stored in a lake and then filtered up into a storage tank…no tap water was used. Another storage tank contained recycled water –the excess run-off after the plants had been watered (which was infrequently).
The height of the roof was pointed out – the airy space resulted in better growing conditions. More light and even temperatures resulted in compact plants. On the day we visited the shades were in place – as they would be in the evening, to conserve the heat. The new facility had condensed the plant growing period, meaning that later starts saved on heating – which was above and below the benches. Everything, from ventilation, to watering, to heating, to operating the anti-glare was controlled electronically.
Currently only 50% of the area has benches, (due to the fall in sterling after the Brexit vote), but more will be obtained. Some areas will be left vacant however, to house hanging baskets and planters of various sizes – those destined for the city centre are about six foot high. Ideally when the facility is complete there will be four growing zones with a two degree temperature variation between each zone, so that plants can be held back or brought forward dependent on the dates at which they are required. As this was the first full growing season on this site, the plants had been bought in from commercial growers as small plugs as it was easier to calculate their start date, working back from the date they are needed. It will be a commercial decision whether to grow more from seed next year – basically whether they can do it more cheaply than the commercial plant growers.
Andrew was keen to stress the environmental-friendly nature of the plant – self-sufficiency in water, little heating and recycling of all the planters used – the manufacturer takes returns to manufacture new stock. Leeds City Council (taking 40% of the production) only use peat free compost, but as this was much heavier than the alternative, the ecological benefits were marginal and it was not used on the retail side. On-site plant sales and 52 smaller contracts (e.g. In Bloom groups, Parish councils, retail site managers- account of 60%, all of which is destined for Leeds. There is little profit to be made in supplying other councils.
We were then taken into the “plant factory” where Lee explained about the four Italian machines on view (there wasn’t a comparable English manufacturer). The first machine was a compost dispenser – a huge slab of compost was inserted (without its cover) and then the compost was raked into the tray-filling machine. The mechanism used by this particular machine ensured the compost was lump free. The tray-filling machine could take trays from a stack (placed by an operator) and throw the compost into a tray, all excess being returned. From there the tray would be conveyed (by belt) into the next machine – the planter. This picked a line of plants from smaller trays (placed by an operator) by the root ball without damaging the plant, when they were deposited in the larger trays. It used four metal “fingers” and a central guiding spike. The machine was very flexible, dealing with different configurations of input and output and doing the calculations itself from the basic data required. When operating at full pace it could plant ten thousand plants an hour, saving days of work – but as demand had increased, staffing levels were roughly the same. Operators took the trays to stack the benches and did visual checks making sure each tray was filled. A separate machine could plant up pots. The whole facility is capable of producing three million plants a year…the whole operation was enormous and impressive. After all the facts that we were giving in the hour-long visit, and the fact it was a lovely warm May bank holiday Tuesday, we were pleased to be able to take the weight off our feet in the café where the hot drink (all tea on our table) and cake were very welcome – the “free” tour had a commercial side!