Should Greenhouse be secured to base?

I’ve put a second hand (third hand) greenhouse on my allotment. I dug a perimeter trench, levelled the surface and built a foundation with two layers of concrete bricks and morter. The greenhouse base has a lip aound the edge which means the frame can’t sit directly on the concrete so I’ve put it on a wood base which the frame sits around preventing movement. However, I’m not sure this would be secure enough in high winds. I’d appreciate any advice on whether this should be fine or to fix greenhouse base to the wood?

The wood is screwed into the concrete.