Planting the topiary in Queen Mary’s Gardens


Will it be yew topiary or pleached limes? After two years of discussion the decision was made in favour of the former and another six months was spent examining photographs from six suppliers. There was enough money in the donations budget and so the plants finally arrive!

The planting needs to look right as well as leaving enough room for the mowers. And so the first new pit is dug, and drainage is going in. No going back now!

The topiary root balls span 1.5 m+ by 0.7m+ and weigh over a tonne causing significant compaction of the soil underneath. As they require good drainage a ‘raft’ of 100mm gravel with a geotextile material was put in the bottom of each pit, and a laser sight was used to ensure all the topiary were in line. The “platipus” ground anchor system used to stabilise the topiary. required a metal skid at the end of the wire driven into the ground. When the driving rod is removed and the wire is pulled on to the skid, it rotates through 90° and acts as a good anchor.

A pneumatic hammer was used to drive the anchors a metre into the soil and the root ball was held in place with straps attached to ground anchors.

To raise the root balls above the surrounding lawns, the soil level had to be built up above the geotextile. Called mound planting it helps plants to avoid sitting in water.

There was about 10cm of brown topsoil over 30cm of rubbly sub soil, probably from the conservatory that used to be on this site. And in amongst this layer we found a significant quantity of oyster shells. Perhaps from working lunches in the early 20th century? or maybe used to make lime for construction or plant compost?

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