embarrassing, but, true
There are many ways to design rose vases. Personally, I would never ever use a grid or tape of any kind for many reasons.
My two favorite ways to secure the greens is to lace each stem in your hand before you put it in the vase. Then you might add some filler or other greens to help support your handtied green base. The other way is to use a base of green such as pittosporum or similar and add the other greens after I create a good basing.
I like to put the shorter roses around the outside of the vase first, weaving them into the greenery base as I go. Then I put the next layer in the middle of the vase until I get to the top and longest ones. If you still feel like you need more support for your flowers at that point, just insert more greens through the stem network you have created.
I promise you that this not only looks better than using grids, but, is much faster and costs far less. Also, I always design my bouquet in one vase (I use this vase for many arrangements) and then transfer it to another one with good clear water and then there is no debris left. You are not able to do this if you use a grid.
I have been in many shops that still use a grid and taught many designers over the country how to do this technique and they never go back to using a grid. If you get good at this, I promise you that the bouquet will not turn or get messed up in delivery. I have never had a bouquet come back to me for this reason in my entire life.
Another popular and desirable way is to make a spiraled handtied bouquet and tie it off with an electric strip or raffia, etc. This does take a little more practice, but, the end result is the best when you really learn to do this well.
Also, not many shops are still putting bows on their dozen roses. This seems to be passe'. And very few are doing one sided rose arrangments.
Carol Bice