What to feed your roses is really a difficult question to answer because it depends on your soil, which can vary a lot within your own garden. Most gardeners report success with given fertilizers and rose foods based upon what they have observed in their gardens .... even the experts because not all variables can be identified and soil make-up varies a lot both in the texture and make up.
Some gardeners never have to feed their plants because they are already gardening in very fertile soil, so the addition of compost and mulch is sufficient to supply the needs of the plants in their gardens.
Others, have to add other fertilzers, either organic or chemical, to provide for the needs of their plants and what works will vary. So most of what we share is what we have found works in our gardens.
I can share some generalities, but it is wise to have a soil test.
Re: Bone meal ... the product sold in the US today is very different than the product that was sold before the mad cow disease scare. It has much fewer nutrients and can provide little benefit to the plants if your soil has sufficient phosphorus already in the soil. Soil particles tend to hold onto phosphorus and too high a level of phosphorus can actually inhibit the uptake of other nutrients needed by the plants. Personally, I think the current product being sold is really not all that useful for growing roses. It may be very good for other plants that have a higher need for phosphorus.
The soil particles do not hold onto nitrogen. The nitrogen you add leaches through the soil beyond the root zone and is not available to the plant. Nitrogen is what feeds the soil the most, but if used in too high of a quantity ... i.e. a high number, it can 1) burn the roots of a plant and thus stress the plant, or 2) it will feed the plant in such a way that you get more foliage than blooms. Also, too much nitrogen will stimulate soft, weak growth and a less sturdy plant.
As compost and mulches placed on top of the soil decompose, they are returning nitrogen to the soil. If, however, you have poor soil, which I did when I first started my garden, adding nitrogen is one of the ways to make both the soil and the plants healthier.
When I first moved to the mountains, I did not have access to many of the good fertilizers now available with lower numbers. So, I had to use what I could get. The numbers were outrageously high. I just diluted it so that the fertilizer I used did not have a negative impact on either the soil or the plants.
Plants also need potassium, which is the third number in most rose foods. For the most part, they don't need much. Zuzu's banana peel placed at the bottom of her rose holes is an excellent source of potassium. In the early years, I used to freeze my banana peels and then in spring run them through the blender and then added water to the mix and gave my roses a banana shake to give them added potassium. Unfortunately, this practice drew skunks to my garden, so I had to discontinue this practice.
In my case, I have magnesium poor soil, so my plants benefit from a dose of epsom salts in spring.
Neal is correct in that it doesn't matter if a plant food is called tomato food or rose food. Roses can't read, so they don't know that they have been given tomato food. It's what's in the food that they respond to for nutrients.
For young plants, I have been taught to "feed often and weakly". This practice avoids the burning of the roots and still provides the nutrient needed on a regular basis.
What I am saying, is we can tell you what we have seen works in our gardens, but you will have to find what works in your garden.
