Hi Krissy. We have 3 rosemary bushes, but they are in full sun most of the day. Also, they get 2 hours of water everyo ther day. During the winter, they get 1 hour every 3 day. Probably, yours aren't getting enough water to develop, or get to, deep roots. I think its is always better to water less often, but deeply, especially when plants are established. Hope this helps.

It sounds like your watering schedule may need some adjusting. The key to irrigation here in the desert is to water deeply but infrequently. As long as your rosemary is established (in the ground 2 years or more) you should only need to water once per week (or less) in the summer tapering to once per month in the winter. Rosemary is native to the Mediterranean so it can cope with hot, dry temperatures.

If you are using a drip system, 30 minutes is not long enough. The recommended length of time to water is 2 hours - that gets the water down deeply into the soil and encourages deep roots. If you have a one gallon emitter on your rosemary, you are only delivering 1/2 gallon of water in 30 minutes- not nearly enough for a shrub. 15 minutes of watering would only deliver a quart of water and may only soak in for a few inches rather than the recommended two feet. Watering too often can cause yellowing leaves and makes it difficult for plants to pull nutrients out of the soil, especially iron.

Your other plants will do fine on the same schedule. You should always water for 2 hours, but just change the frequency. I water my shrubs once every 10 days to 2 weeks in the summer, once every three weeks or so in the spring and fall and once a month in the winter.

Here's a link to a watering schedule for established plants. At the bottom is a schedule for newly insttalled plants.

Here is a link that might be useful: Watering Guidelines

I am getting white foamy beads forming on my rosemary bushes. they are about 1/4 inch to 1/2 inch in size. Do you know what these are and are they harmful to the plant?

I read the foam comes from a tiny parasitic insect that is harmless.
I only water about once a week and much less in winter. Mine is in full sun. How long do they take to bloom? I've heard they are good bee attractors but mine is green, never blooms. It's about 18 months.

yeah I water mine once a week if I remember and they look good. Mine haven't bloomed either, I've seen some that bloom with beautifull little blue flowers. I wish mine would do that. I don't think the op's problem is too little water. maybe too shallow, too often. my experience with rosemary is that it thrives on neglect. Personally I would use a little compost tea to give it a boost. I haven't seen many plants that don't benefit from that.

Rick - the foam is from a "spit bug" ... just hose the plants off occasionally.

The blooms will come as the plant matures. Give it time. And give it more water per watering, but less often.

The white foamy beads are from an insect called Spittlebug which looks like a tiny leafhopper. The immature nymphs secret the foamy lather to protect them from predators. They don't seriously harm woody plants but can do a little damage on young herbacious ones. Just spray with a strong stream of water to dislodge them. In extreme cases you could try a soapy water spray made from 1 teaspoon liquid dish soap in a gallon of water.