Yes, Tempo SC Ultra does kill fleas. Its active ingredient, beta-cyfluthrin (11.8%), is a synthetic pyrethroid that targets the flea’s nervous system, causing paralysis and death. Fleas that contact treated surfaces typically die within 1 to 24 hours. However, Tempo has a significant limitation: it only kills adult fleas and larvae, not the well-protected pupal stage, which means a single application rarely eliminates an entire infestation.
How Tempo Kills Fleas
Beta-cyfluthrin works both as a contact poison and a stomach poison. When a flea walks across a treated surface or ingests the chemical, it disrupts normal nerve signaling, triggering constant muscle spasms. The flea becomes paralyzed and eventually dies. This “knockdown” effect is relatively fast compared to some other insecticides, but it isn’t instant. The flea needs to pick up a lethal dose first, which is why death can take anywhere from one hour on the quick end to a full day.
Where and How to Apply It for Fleas
Tempo SC Ultra is labeled for flea control on outdoor turf and perimeter areas. For fleas and ticks specifically, the label calls for a concentration between 0.025% and 0.05%, which translates to 8 to 16 ml (roughly 0.27 to 0.54 fluid ounces) per gallon of water. You apply it at a rate of 8 to 16 ml per 1,000 square feet of treated area.
The label directs you to make a perimeter treatment and concentrate on areas where pets rest or run, since those are the spots where flea populations build up fastest. Approved application sites include home lawns, apartment complexes, parks, playgrounds, athletic fields, and other landscape turf. It is not labeled for golf course turf or commercially grown turf.
After mixing, spray the solution evenly across the target area using a pump sprayer or similar equipment. Allow the treated surface to dry completely before pets or people re-enter the area.
Why One Application Usually Isn’t Enough
This is the part most people miss. A flea infestation involves four life stages: eggs, larvae, pupae, and adults. Tempo kills adults on contact and can reach larvae in exposed areas, but the pupal stage is a different story. Flea pupae develop inside a sticky, silk-like cocoon that shields them from insecticide sprays. The pupal stage normally lasts 7 to 14 days but can persist much longer under certain conditions, with the developing flea essentially waiting inside its protective casing until it detects a host nearby.
Fleas sitting in the pupal stage when you spray will frequently survive the treatment and emerge days or even weeks later as fresh adults. This is why follow-up treatments are almost always necessary. Plan on reapplying Tempo at least once, roughly two weeks after the first treatment, to catch newly emerged adults before they can lay more eggs.
Tempo Alone Won’t Clear a Full Infestation
Because Tempo is an adulticide (it kills mature and active-stage fleas), it doesn’t contain an insect growth regulator, or IGR. An IGR mimics flea hormones to prevent eggs from hatching and larvae from developing into adults. Without one, the cycle can restart every time a new batch of pupae hatches out. Pairing Tempo with a separate IGR product gives you a two-pronged approach: Tempo handles the adults, and the IGR breaks the reproductive cycle.
Outdoor spraying should also be combined with indoor measures if fleas have made it inside your home. Vacuuming carpets, rugs, and upholstered furniture is one of the most effective ways to physically remove eggs, larvae, and pupae from indoor environments. Vacuum frequently and dispose of the bag or canister contents immediately. If your pets are the source, a veterinary flea preventive applied directly to the animal is essential. No amount of yard treatment will solve the problem if untreated pets keep reintroducing fleas.
Mixing Ratios at a Glance
- 0.025% concentration: 8 ml (0.27 fl oz) per gallon of water
- 0.05% concentration: 16 ml (0.54 fl oz) per gallon of water
- Coverage rate: 8 to 16 ml per 1,000 square feet
Start at the lower concentration for light flea pressure and move to the higher rate for heavier infestations or areas with dense turf where the spray needs to penetrate deeper.
Safety Around Pets and People
Beta-cyfluthrin is toxic to insects at very low concentrations, but it still requires careful handling around pets and children. Keep people and animals off treated surfaces until the spray has dried completely. Cats are generally more sensitive to pyrethroids than dogs, so be especially cautious about allowing cats to walk on recently treated areas. Never apply Tempo directly to an animal’s skin or fur. It is designed for environmental treatment, not as a topical flea product.
Store the concentrate out of reach of children and pets, and avoid spraying near fish ponds, streams, or other water sources. Pyrethroids are highly toxic to fish and aquatic invertebrates even in small amounts.