In your zone the purpose of planting the graft below the ground is winter protection. If you plant the graft 4 to 6 inches under the soil if the rose dies back in winter all the way to the soil you will not lose the graft and have the root stock take over. Otherwise you will need to protect the graft for winter or take the chance of losing your rose. If the rose is planted well, in a good spot with good soil and plenty of sun, and well cared for with water and fertilizer it should be fine. It's very hard to determine exactly when a rose will bloom or how long it will take a rose to bloom. It depends on each variety. For exhibition purposes sometimes we'll keep records of how long a particular variety takes to cycle and prune accordingly before a show. It's usually somewhere between 6 & 8 weeks before a show. Then we just hope that the roses will bloom at just the right time. Sometimes it works but not always. There are no guarantees.

Andrea, I prune my mature HTs to around 18" every spring when growth starts. For tall-growing varieties like Frederic Mistral and Elina, I may spring-prune to 12" once they have developed a whole lot of basal canes. However, I understand most California growers prune to 24" or 30", so I guess they find they get more flowers that way. Understand that I don't have experience in California--but, If you think Pristine's bare knees are unsightly, I think you could cut her back to 18" at the end of spring or summer flush, but then she'll be bare for three weeks. The caveats that occur to me are that green bark could sunburn if it is very hot, and, if you don't irrigate much during summer drought, that could interfere with refoliation. Of course early next spring would be fine.

Your zone is very different from ours so I don't know how to answer that question. I won't use a bloom booster except as I described above to get blooms during a rare summer cold front. The reason is that our weather is so hot in the summer that the plants stop setting fruit. In fact, at our house this week, in just a couple of days, we move into that danger zone of temperatures in the mid-90s. Hopefully we won't stay there. I'd hate to think the tomato plants have already set all the fruit they are going to set this spring/summer. If your tomato plants are blooming and your daytime highs are staying below around 92-95 and your nighttime lows are staying below 70-72, you shouldn't need a bloom booster. Your plants should bloom naturally and should set fruit. I haven't used a bloom booster in years because even though our summers routinely are very hot, I usually don't need a bloom booster unless we are in prolonged drought, and we haven't had prolonged summer drought at our house since 2015, which is extremely rare. If your tomato plants are blooming and not setting fruit, perhaps your nights still are too cold (below 55 degrees). Or, if you are having normal weather and fruit should be setting in the temperatures you have but it is not, then perhaps there is a lack of wind to shake up the flowers. Tomatoes have perfect blossoms and the flowers need some movement in order for the pollen to fall from the anthers inside the flower to the stigma, also inside the flower, to achieve pollination and fertilization. If your air is very still or if wind movement is blocked by something like a building, your plants may need some help moving. There are various ways to do this. The traditional one is to thump the flower blossoms. If you have a lot of plants and they are caged, you can just walk along a row of cages giving each cage a gentle shake as you pass by. Or, if you have a tennis racket....walk along the row of plants with your tennis racket in your hand. Give each tomato cage a good whack as you walk by. That will cause the plants and their flowers to move and the pollen to move around inside the flowers. You can use a bloom booster whenever you want, but don't overdo it. Too much can cause too much fruit set and then the plant has more fruit than it can carry to maturity.

Nice to see some flowers! Spring is coming :)