The birth of solo backpack sprayers found it’s beginnings when the Solo Company was founded in 1948 in Germany by a pair of entrepreneurial brothers, Heinz and Hans Emmerich.
The two set out to develop an industrial lightweight, two-stroke engine that would make an improvement over the current 35-pound “lightweight.” Their final result weighed in at a little over 14 pounds and produced 1.2 horsepower.
In the next two years, the successful brothers developed prototypes of innovative lawnmowers, water pumps, scooters, and more. Their first backpack sprayer got constructed in 1950. However, the sprayer did not work for liquid products, but rather, people used this as a light dusting machine.

This machine still exists and appears available for public viewing in Munich Museum.
Today, this well-established company produces a full line of high-quality backpack sprayers featuring competitive pricing and top-of-the-line capability. In this article, we will discuss the merits of these high-quality backpack sprayers and provide brief reviews of each model offered by the company. Read on to learn more.
What Can You Expect From Solo Backpack Sprayers?
These sprayers range in capacity from 2 gallons to 6.6 gallons with the 4-gallon size as the most popular as you can carry and manage it easily.
The 4-gallon capacity accommodates enough spray solution to work for a long time uninterrupted and without fatigue. For this reason, some sellers offer several models in 4-gallon size.
The Solo Backpack Sprayer tank design appears unique. You can always recognize these sprayers by their rounded and comfortable shape. They look more than just a “pretty face,“ though!
In addition to their good looks, they also exude exceptional durability with rugged, high-density polyethylene tank. These sprayers can resist chemical damage and come with a full one-year warranty.
All Solo sprayers come with a handy collection of nozzles:
- Adjustable
- Jet Stream
- Flat Spray
- Hollow Cone
With this complete collection, you can accomplish any spraying task. Every unit comes equipped with in-line filters, screens, and strainers to keep the nozzles debris free for smooth, continuous operation.
The wand coming with each model does not break, and only top quality Viton® O-rings, gaskets and seals get used throughout.
The handy Pressure Regulating Valve allows you to select from four levels of pressure: 15, 30, 45, or 60 pounds per square inch. All pressure regulator models come comfortably equipped with adjustable padded shoulder straps for easy fit and pain-free use.
Where Can You Get Solo Backpack Sprayers?
The company holds over a thousand distributors across the nation. For most people in today’s fast-paced, connected world, online purchase serves as the easiest, and often the most affordable method. Some online retailers carry these products such as the below Amazon’s top picks.
Solo 425 4-Gallon Professional Piston Backpack Sprayer

This four-gallon, piston pump-style sprayer is quite comfortable to wear and use. The product is well-balanced, and you can easily access the pressure pump handle. The 3-4 gallon capacity keeps the weight under control making it an excellent choice for use on larger properties or properties with the uneven or hilly terrain.
The balance of the backpack design makes it preferable to a handheld or single shoulder carry unit. This easy to use tool works great for applying on-the-ground or foliar fertilizers to small acreage. Furthermore, the four-gallon size provides enough capacity to cover a couple of acres without having to refill.
For foliar applications in trees, purchase a longer wand. The ability to lock the unit in the ON position makes high foliar application easier.
Some users complain about the unit getting stuck in the ON position. To solve this problem, remember to release the lock occasionally and take a short break.
Adjust the tension clamp holding the wand o prevent leaking. Close attention to the amount of pressure in the tank is also important. Moreover, too much pressure can cause leaking.
All things considered, with careful attention to care and maintenance, this lightweight, durable model makes a versatile and useful tool. Also, this product appears as the top choice of professional gardeners, nurseries, and arborists. Users find it easy to maintain, repair, rebuild, and even upgrade as needed, which means this unit delivers a great deal of value on a long term basis.
Learn More or BUY The Solo 425 Backpack Sprayer
Solo 475-B Professional Diaphragm Pump Backpack Sprayer, 4-Gallon

This four-gallon, diaphragm pump sprayer makes an excellent choice for a large acreage. Users who tried piston type sprayers in the past and upgraded to this diaphragm model felt pleased with the improvement in ease of use and efficiency. When compared with other brands of 4-gallon, diaphragm pump sprayers, this model proved to surpass others in terms of durability and resistance to leaking.
With this diaphragm pump sprayer, you can get a maximum amount of spray coverage with very minimal pumping. The ability to choose from a variety of nozzles also gives you a great deal of control over the amount of area you can cover. The unit comes with the standard five nozzle selection, and you can purchase more from Solo or your local garden center.
The diaphragm pump provides adequate pressure to deliver spray to a distance of up to twenty-five feet. If this does not satisfy, you can also buy an optional high-pressure hose kit to deliver even more power.
Generally, this user-friendly assembles quickly, and storage comes easy. It comes with a useful carry handle and comfortable padded straps.
Some users find the waist strap ineffective and unnecessary. On the other hand, some users also find the unit too heavy when filled. Users can make use of two easy workarounds for these:
- Don’t fill it all the way!
- Set it on a table or other waist-high surface when easy filling and simply back up to it to put it on. This way, you will not need to rise from a squatting position with the filled unit on your back.
Learn More or BUY The Solo 475B Diaphragm Backpack Sprayer
Solo Battery Powered Backpack Sprayer, Large, Translucent
This rugged, well-made 4-gallon unit holds a battery powered diaphragm pump. Users find it very comfortable, easy, and efficient to use. Pumping only a time or two results in long-term spraying covering large areas quickly and effortlessly.
This professional sprayer works like an absolute champ regarding leak control. In fact, users report no leaks at all.
The Spray Nozzles Makes Covering Large Areas Easy
Although it does not come with the great nozzle assortment like the other Solo units, its four-nozzle assortment functions supremely with the flat, fan sprayer touted as an excellent choice for all-around applications.
While tip removal and replacement feel a bit fiddly, when you use this adjustable nozzle, you will no longer require any changes. The spray pattern ranges wide and makes covering large areas quick and easy.
This unit makes a good equipment for application of pest control products and weed killers. It contains a wide mouth making it easy to measure water and chemicals directly into the tank. Because of the diaphragm pump, you can use harsh chemicals such as herbicides and pesticides.
This means great savings for homeowners who wish to perform their own pest control, as opposed to hiring a professional service.
Buying concentrates of Neem oil pesticide for a typical yard, and home chemicals serve as a real money saver in itself. Moreover, performing the application yourself will also save you a ton of money.
As with the other 4 gallon choices, this unit can weigh a bit heavy. However, following standard workarounds should help counter this problem. Some users find the wand too short, but longer versions do exist.
Battery power means constant, effective pressure. You will not need to make use of the pump handle to increase pressure as long as you keep your battery well-charged. The battery also turns the pump off and on in response to your use.
You will notice vibration, but no noise will come out.
Having battery power and constant pressure makes it possible to cover large areas quickly and easily. You can typically spray about fifty gallons of solution before needing to recharge the battery.
Unlike some sprayers shutting off when the tank approaches empty, this sprayer continues to operate and empties the tank completely. After releasing all the liquid, you will hear the pump running continuously, and you will notice that nothing is coming out of the wand.
When the load runs out, you can simply reach back and flip the OFF switch without having to remove the backpack. After working, add a half gallon of clean water to the tank and disperse it through the sprayer to clean the unit.
Some users complain about the positioning of the hose as it leans a bit awkward while it comes from the center of the unit rather than from either side. Also, they say this position makes it difficult to get hold of the wand when the backpack is in position.
Moreover, some users complain about the seal on the lid not holding enough. This results to a few leaks if you bend over. However, this problem apparently resolves itself over time as you utilize the unit more and more.
Learn More Or BUY the Solo Battery Powered Backpack Sprayer
Solo 451 3-Gallon 66.5cc 2-Stroke Gas Powered Backpack Mist Blower
This gas powered, three-gallon, diaphragm pump backpack mist blower makes a popular choice all around and comes as especially useful in commercial settings. Professional gardeners, landscapers, home maintenance crews, parks and rec workers and nursery workers report dramatically shortened time while performing daily tasks.
In some instances, tasks formerly taking several hours now finishes within an hour when using this unit to disperse a fine mist of solution over a large area. This type of solo backpack sprayer work perfectly with delivering disinfectants and pesticides for tick, flea, and mosquito control.
This unit appears supremely dependable and starts up readily, time-after-time in all sorts of weather with no problem. It comes as a lightweight, durable and efficient equipment. However, some users say that it lacks balance to carry and feels challenging to lift with a full tank.
Even so, for dependability and speed, this unit comes out as the top choice.
Learn More or BUY The Solo 451 Gas Powered Backpack Mist Blower
Go With The Established Pro!
Solo emerges as the leader in small engine and agricultural equipment production since the mid-20th Century. Today, the company produces a full line of high-quality, trusted products with solid warranties, and 24-hour customer support via their website: Solousa.com
The company offers its time-tested products through more than a thousand dealers across the USA. Thanks to over seven decades of experience and success, you can feel confident about getting a machine standing out regarding performance, comfort, safety, price, and customer service when you choose Solo Sprayers.