Anchors. Essential to prevent being dislodged - even heavy glass frames are susceptible to high winds when a vent is ajar. Bolts are good for fastening a frame onto a solid base; ground pegs for soil. Often anchors are included with the frame but you may need better ones.

Materials for repairs or diy. Try Two Wests & Elliott for all sorts of supplies.

Shading, vent openers, shelving, watering, thermometers... Two Wests & Elliott have a range of goodies for greenhouse growers.