This morning I found this info on a Roanoke Times gardening blog.. Great info!
Fanatical Botanical: 7 Mid-season gardening tasks
By Heather O’Bryan
July is a crucial month for gardening. There are several key tasks that must be performed to keep your landscape looking its best. Below is a small list of what to do for that mid-season maintenance.
Mums – If you have mums planted in the ground, now is the time to prune them so they bloom in fall. Take some hedge clippers and cut them halfway back. This will cut off any blooms growing now, encourage new growth and double the amount of blooms in fall.
Knockout Roses – These shrubs also like to be whacked back around this time of year. Use those same hedge clippers to cut them by half. If they are in a blooming cycle right now, wait until the blooms start to fade before cutting them.
Perennials – Some perennials are just now flourishing while others, like the spring bloomers, are looking spent or even dying back. Prune these undesirable looking plants to an inch or two above the ground. If there is fresh growth near the crown, prune just above that.
Spirea – Spirea can get huge in the middle of the warm months. Luckily, it responds well to heavy pruning. If your spirea needs a haircut, don’t be afraid to cut it really short, particularly about a foot or two from the ground. Don’t worry, it will flush out and look more beautiful for it.
Annuals – If your annuals are getting leggy, prune them back by half and feed them well to flush out new growth and blooms.
Daylilies – Keep an eye on your re-blooming daylilies. They will begin to put out seeds, which are round and plump looking. Pinch these off so the plant will keep putting out blooms. This is a great chore for kids.
Herbs – Pinch off all blooms on your annual herbs to keep the fresh flavor going. Once they flower, the taste changes, becoming more intense or even bitter in some cases.
Perform these tasks this month and you’ll have a much nicer looking landscape during the growing season.
I’ll personally add to the list, if you have Montaulk Daisies, they need to be pruned really around June 1st, but I’ve done them this late, about 1/2 their size, in early December also, they need to be cut to about 2″ from the ground. In both cases the cuttings root easily, just dig a hole and put them in!