If you are asking about Fertilome Weed free Zone with 2,4 D the label suggests the the product will harm ornamentals. Part of the label shown below:
Do not allow spray drift onto Vegetables, Flowers, Ornamental Plants, Shrubs,
Trees and other desirable plants since injury may result.
• Do not exceed specified dosages for any area. Be particularly careful within
dripline of trees and other ornamental species.
• Do not apply as a fine mist because of potential injury to desirable plants.
We recommend to contact the master gardener for a product recommendation that works in your area to safely treat around the tulips. Here is the link http://www.csrees.usda.gov/Extension/index.html
If using a Scotts Broadcast Spreader when applying Ferti-Lome Weed Free Zone Plus Lawn Fertilizer 18-0-6, the setting should be at 4.5. Each bag will cover 7,000 sq ft and is applied at 2.5-3 lbs per 1,000 sq ft.
The Ferti-Lome Weed Free Zone Plus Lawn Fertilizer 18-0-6 product label specfically states not to use on St Augustine lawns. Ferti-Lome Weed-Out Plus Lawn Fertilizer 25-0-4 could be used, if your lawn needed this amount of fertilizer and is not Floratam or another improved variety of St. Augustine. We would recommend taking a soil sample to your master gardener to get it tested. Once you know exactly what your soil is lacking, we will be able to make a proper recommendation for you in regards to fertilizer. For St Augustine lawns this product is applied when weeds are actively growing, this is typically April - May.
Ferti-Lome Weed Free Zone Plus Lawn Fertilizer 18-0-6 is not labeled for crabgrass.
Per the label, Ferti-lome Weed Free Zone Plus Lawn Fertilizer 18-0-6 should be applied early spring or early fall. As soil temperatures cool, it will be harder to see results. We recommend contacting your local extension office regarding application timing in your area.