Plants can't use fertilizer until a good number of leaves are fully expanded and green, so that's when I usually fertilize. However, organic fertilizers need to break down, so if you apply earlier, the nutrients wouldn't be wasted.

It's often recommended to apply a little fast nitrogen (manufactured source rather than organic), because even in rich soils, available N may be scanty as long as the soil is cold and wet. Otherwise, the season doesn't matter particularly.

I haven't used worm castings, but I'm sure they are fine.

To prepare them well for the winter, you should not forget to fertilize in autum with a potassium rich slow-release fertilizer: potassium helps them become stronger. For instance: NPK 8-5-25

Now they probably need more natrium and phospohurus. For instance, somenthing like NPK 20-10-8

I personally prefer to use a balanced slow-release fertilizer NPK 15-9-15 which is fine both in spring and in autumn

My roses are doing what yours are. I used organic fertilizer, a granular..and I used some worm castings..dug it in around the roses and I am planning on using some fish fertilizer..but I am going to use 50% of the dose it says to use. I will do it again in 2 weeks.

I use PB Natural Rose fertilizer, and the manufacture recommends to feed 2 weeks before last freeze date. Last freeze date here is 15 Apr so I just fed them.

All my roses have been leafing out for the 2 months so in mid Feb I, like Zyperiris started to give them half strenght of fish emlusion and they are all doing great.

I'm going to prune some time this month, and I'll put down the Holly-tone at the same time. I'm a slacker, I would rather do both (prune & fertilize) in one pass through the yard.

I fed everything last week with Rose Tone. Alfalfa too. I've been pruning since the beginning of March.

I suppose it depends upon how warm the zone you're in, but, in zone 6, I would never give roses any fertilizer past mid-August. NEVER. They don't need to be encouraged to grow when they should be settling down for the winter. It does them more harm than good.

Zone 5 fertilize 6 weeks prior to first expected freeze date.

You don't want to fertilize until the leaves are the size of the first joint of your pinkie finger. Then, give them a well-balanced, non-weed and feed formula. Spread around the drip line, water, and scratch in well. I also give mine some Osmocote, Sierra Blend. This is a peletized, slow release fertilizer that will not kick in until the soil temp is around 70 degrees. This can even go in before leaves appear, because, as noted, it won't kick in right away. Roses are heavy feeders during the season, so vary what you give them. They don't care what it is as long as they get something every month.

I use lots of organics, but I also use urea and osmocote as well. I always apply after spring pruning. I've used milorganite, alfalfa pellets, cottonseed meal, processed chicken manure, green sand, lime, gypsum, and epsom salts. I know many people like to Mill's Magic easy feed as well.

Because I have to cut low also, mine will get Miracle Gro For Lawns 36-0-0. This usuallt shoots them out of the ground nicely and by mid May they are 5-6'tall.

Hey Jane, since you have dogs it would be wise to avoid fish emulsion and organic fertilizers containing bone meal, feather meal and blood meal (check labels before buying products). I'm using Osmocote, works fine. Dan's suggestion of lawn fertilizer is also good -- its cheap and effective. I don't think dogs are interested in worm castings, those shouldn't inspire much digging.

Regular Turf Builder or generic substitute also works fine for a nitrogen booster. I use the Ace Hardware brand, no more than 1 TB per full square yard.

Everyone is just guessing, since no one knows a thing about your soils. We're not growing corn! Adding complete fertilizers without a soils test is a crap shoot, pure and simple. Yes, most soils will need some kind of nitrogen early in the season. A modest amount of nitrate nitrogen works well. As for phosphorus and potassium, it really depends. My roses don't need it at all, so paying money for fertilizer they don't need is a complete waste of money. Many fertilizers have increased in price two to three times over the past two years.

If a soils test isn't possible, and often you're told nitrogen can't be measured (then I don't know how my soils chemist does it), get a general idea from the local agricultural extension office which fertilizers are generally needed.

Here is a link that might be useful: UConn soils testing

I agree with bern...get a soil test. They usually aren't expensive. In fact, your extension office may provide that service. However, they may not be the fastest to get your results.