Buy the Semaspore and spread it. Check the container before you buy it and make sure it hasn't expired. Because the microorganism (Nosema locuste) that serves as its active ingredient is a living being, the product has a limited shelf life and an expiration date. You can prolong its life by keeping the container in the fridge. I usually keep mine in the extra refrigerator out in the garage. If you can find it locally that is great, but it is incredibly hard to find in local stores. There's a couple of reasons: (a) it has a very limited shelf life, (b) it is somewhat pricey, and (c) when a severe grasshopper outbreak occurs, everybody runs to the store to buy it and the 2 to 4 containers of it on the store shelves are gone by the time you or I get there. Your best chance of finding it would be at a local (not chain) feed and seed or farm store, or at a garden center/nursery that specializes in organic products. I've never seen it in any store in my part of OK or in adjacent parts of western North Texas, and usually have to drive to the D-FW metro area, where I may or may not find it there.

This year, when I needed it, I ordered it from a very reputable supplier of organic products called Arbico Organics. I hate spending money on the shipping, and their shipping is expensive, but I had the product in my hands within about 3 or 4 days of ordering it, I think, so I was happy. That sure beats waiting weeks and weeks for some less diligent firm to finally get around to sending it to you long after you really needed it. Been there. Done that. Wasn't a happy camper.

This product is most effective on small hoppers in the early instars, and not nearly as effective on older ones so I usually use it only in April or May. However, with June being cool and mild so far, if you can find it and use it within the next week or two, it ought to be pretty effective. If we get the sort of relatively cool and mild June weather that is expected, that would be terrific because it gives us more time to fight the little hoppers as they are hatching, which is much more effective than fighting big, migratory ones that fly in later in the summer.

Be careful about buying online. I have ordered online twice in recent years only to have it inexplicably take a month or two to arrive, and to have it arrive one week prior to its expiration date. I've never ordered from either one of those companies again, figuring that if they don't pay close attention to important details, like product expiration dates, then they don't deserve my business. I actually gave the late shipping company a second chance, and on that order for beneficial insects that I needed right then, they never did ship them and the company and I had some angry words a couple of months later when they couldn't even explain why they never filled my order. Prior to that I had purchased a lot from them and recommended them regularly here on this forum. I still might occasionally link one of the insect or product info pages here because they do contain good info,but I don't out and out suggest to anyone that they should purchase from that company because I'm not going to stake my reputation on a company that has severely disappointed me on multiple occasions. I don't like to order Semaspore unline unless it is from a company I really, really trust will send me the right product, and also I trust them to not send me a product that's about to expire. With some products, it doesn't matter so much, but with one you need at a specific time and that you need to not expire almost before you can even begin using it, I'm picky.

Some people have had some success with spraying young (but not big) grasshoppers with a commercial insecticidal soap like Safer Insecticidal Soap, but I don't even bother. I don't like spraying soap sprays on plants that will be exposed to hot sunlight and high temperatures and spraying the entire garden is incredibly time-consuming.

I also have used EcoBran, which is very effective but pricey, and I doubt I'll go that route again because I no longer purchase from the US company that carries it. (I think it is a Canadian product.)

Some people who are members of this forum have used Malathion to kill grasshoppers and seemed pleased with how well it worked, but I won't use Malathion. One year, and this is the only time in my life I've ever sprayed my entire garden with a synthetic, broad-spectrum insecticide, I sprayed for grasshoppers with a chemical pesticide product which I normally avoid using and it did kill them, as well as every other insect in the garden at the time. I hated doing it and was careful to spray after sunset when the bees were gone. At the time, it felt essential to do it because the hoppers were eating my tomato plants down to naked stems and I was desperate to save the tomato plants. If I had it to do over again, I wouldn't have sprayed that pesticide. I think I just would have closed the garden gate and walked away and abandoned it for a couple of months and then resumed gardening in the fall after the hopper population fell naturally. I could smell that pesticide in the garden for weeks and hated even going into the garden. We had an aphid outbreak on melons, likely because the chemical pesticide had killed the ladybugs so no one was controlling the aphids, and then sooty mold broke out on the melon plants because of honeydew from the aphids. It is exactly those sorts of unintended consequences that make me hate using synthetic chemical pesticides, and I hope to avoid ever doing it again. And, of course, as grasshoppers are prone to do, a whole new bunch of them flew in a week or two later. We were in the midst of a multiyear drought and the grasshoppers are much worse in years like that than they are in wetter years. Desperation will drive a gardener to do things they normally wouldn't do in an effort to save their plants, but I hope I learned an important lesson that summer. Nowadays, I'd probably put insect netting over the most important plants instead, but hindsight is 20-20.

Normally, I just ignore grasshoppers and the damage they do except when they show up at huge numbers.

Some years I have felt the Semaspore wasn't working, only to have Fred tell me that even if I thought we had a lot of hoppers, that he felt like we had very few at our place compared to other folks nearby like him. Even my non-gardening then-daughter-in-law remarked one day that when she drove down our road, grasshoppers flew up out of the bar ditches in huge numbers except at our place, where they didn't. So, Semaspore has worked well for me but it isn't an instant kill and it won't kill them all because some of them won't eat it. It normally does reduce their population to low enough numbers that you see the level of damage decrease.

Hope this helps.

Thank you, Dawn. I doubt we have anything resembling organic in Shawnee, so I'll be ordering from Arbico.

You're welcome. Arbico's shipping is high but I don't mind it as much as you'd think. I would spend just as much money running around to 15 nurseries in the DFW metroplex looking for Semaspore, so I'd just as soon send the money to a reputable supplier and save the wear and tear on the car. I found some Semapore in a highly reputable nursery once and was so excited to see it, until I flipped the container around to see the expiration date and it had expired months earlier.