The bubble bowl centerpiece design is easier for someone new to flower design if they create a grid on the lip of the opening. Remember to use the clear florist tape, as the waterproof florist tape shown in the photos below was for easier to see photos.
After making sure your bowl is clean and dry, begin taping your grid across the lip of the bowl.
The grid helps keep the beginning flowers stay in place as you insert them into the bubble bowl. Just take the tape down about 1/2" or so on the lip. The clear tape is concealed easily when used on clear glass.
Now tape a contrasting strips across the ones you made earlier. You may want to take it a little farther and tape over the ends by taping over them and going around the entire opening of the vase.
Now it's simply a matter of inserting your flowers into the grid pattern. For a tight, compact flower design, keep the stems shorter. For a larger design, you can extend the stems longer. Just note that it may require more stems of flowers for the larger design.
Place a second focal flower opposite the first.
Now place your third flower at a 90 degree insertion point from the first flowers.
Now complete your pattern and insert another Gerbera across from the third flower.
Add your fifth focal flower straight down the middle, with the flower facing upwards.
Notice how the stems themselves are forming a grid pattern of their own. These stems will help hold the center flower upright and straight.
Take care after designing to check from the side and be sure all cut stems are under the water line, or any flower above the water line will wilt quickly.
Here's a top view of the stems already inserted into the vase.This design is very symmetrical - with all the flowers balancing each other. If you don't wish for such a perfect look, check out my other bubble bowl tutorial for inserting a mix of flowers at random.
A 3/4 view shows we still have a lot of open space that needs to be filled in to look complete.
There is room for four standard roses in these open spaces. A contrasting color will make the centerpieces pop and stand out more.
To finish all you need is a few leaves of Dusty Miller tucked in from the sides, in between the other flowers or anywhere there is a gap. Be sure the cut end of the Dusty Miller leaf reaches the water, as they will droop quickly without a water source.
Watch your water levels, as fresh flowers drink more than you may realize. Replenish the water as needed.
In addition to Crystal Clear Flower food, I highly recommend you use a flower sealant such as Finishing Touch. This seals the petals and slows moisture loss in air conditioned rooms or home refrigerators. These type of cooling units remove moisture from the air, while a professional florist cooler adds a great deal of humidity to the air. Finishing Touch will help compensate for this loss of moisture.