The 4 Best Seed Starter Kits

Growing Medium: Variety | Dimensions: 22.4" x 11.6" x 8.6"

The Super Sprouter Premium Heated Propagation Kit is a superb seed starter kit. After two weeks of closely monitoring our seedlings' progress, it was clear that this model is the way to grow. Our Super Sprouter seedlings showed a 100% survival rate and were some of our largest and happiest-looking babies out of all the kits we tested. We love that the Super Sprouter kit included a miniature grow light and a heating mat, and that the humidity dome has integrated adjustable vents to keep your seedlings not too wet, not too dry, but just right.

There are a few minor drawbacks to consider with the Super Sprouter. This kit does not include a growing medium or planting tray, which may not matter for more seasoned growers who already have a preferred medium or tray, but new growers will need to choose their medium and seed tray separately. Also, this kit is pricy, but as it includes the light and heat mat, we think the price is worth it, especially if you don't already have those at home. This is an excellent kit, one of our favorites, and we'd recommend it to beginners and experts alike.

Growing Medium: Soil Pellets | Dimensions: 12" x 10.5" x 2.75"

The Burpee Seed Starter Tray isn't exactly the fanciest seed starter kit out there, but it's affordable, and it does a solid job. After fourteen days, 100% of the seeds we sowed sprouted though we must admit the seedlings weren't quite as big and healthy as some of the top models. We like that this version includes soil pellets, so as long as you don't mind using natural light and you're not worried about a heating mat, the Burpee Seed Starter Tray is a complete kit.

Although it's great that the Burpee Seed Starter Tray includes a growing medium, we found that the task of moistening and breaking the soil pellets apart was arduous and time-consuming compared to other planting materials. This model lacks humidity vents, so if the dome accumulates too much condensation, you're going to have to get creative with propping the lid up unless you want to remove it. Despite these few minor drawbacks, we still think this is a great model considering the cost and performance.

Growing Medium: Variety | Dimensions: 15" x 9" x 7"

If you know that you'll be using your kit repeatedly or that you're hard on your gardening equipment, check out the EarlyGrow Medium Domed Propagator. This model is made of thick plastic, and EarlyGrow claims that it will provide years of use. Some domes have vents that are a bit cheap and sometimes pop off or are difficult to use, but the EarlyGrow vents are beefy and easily operated.

If you want a complete seed starter kit, the EarlyGrow falls a bit short. You'll have to purchase planting cells or cups separately and provide your own growing medium. During our seedling progress observations, only 50% of the seeds sown sprouted. Still, we think the EarlyGrow Medium Domed Propagator is a great choice if you want a kit with an extra sturdy tray.

Growing Medium: Soil Pods | Dimensions: 10" x 4" x 4"

At only four inches wide and ten inches long, the Window Garden Seed Starting Kit is perfect for a windowsill or other small area. We are big fans of the soil pods included with this model — they quickly expand after being soaked, and indents in the tray ensure that they stay in place. Once expanded, we found that it was easy to plant into the pods. This kit includes three trays, allowing you to germinate a similar amount of seeds to many of the bulkier, gaudier models. During our seedling growth assessment, the Window Garden Seed Starting Kit showed a 100% survival rate, although the sprouts were not quite as big as a few of the other models given the same amount of time.

The main drawback of the Window Garden Seed Starting Kit is that it lacks humidity vents. This is a quick fix, though — simply find a way to slightly prop the lids up, which is easier to rig up on these smaller domes than the larger models. Another problem we noticed is that the Window Garden requires that you use a specific soil pod size, so you'll be ordering more of this type if you use them. That said, if you'd prefer a different growing medium, you're simply out of luck. Despite these small flaws, we love the easy-to-use pods and the fact that this model can fit into tight places.

Growing Medium: Variety | Dimensions: 15.1" x 9.5" x 7.5"

Many green thumbs swear by using a heat source below their warm-season seedlings (think tomatoes, peppers, and basil), but this extra bit of warmth is usually provided by an external heating mat. The iPower Heated Seed Starter eliminates the need for an external source of warmth thanks to its integrated, self-regulated heater. This model has a solid feel and construction compared to much of the competition. While some other humidity-trapping domes have their vents on the lid's sides, the iPower has its single vent located on top. We've found that top vents allow for excessive moisture to escape more quickly, allowing your babies to receive dry air if they need it.

Unfortunately, the iPower Heated Seed Starter does not include a growing medium. The propagation tray cells are somewhat of an awkward size, which means you'll likely wind up using soil for your medium, which most gardeners find preferable anyway. The iPower is also moderately expensive. Then again, you're paying for a heater too, which makes it worth the price.

Growing Medium: Coconut Fiber Pellets | Dimensions: 21" x 10.5" 2.75"

If you're the type that likes to “set it and forget it,” you might want to go with the Burpee Self Watering Seed Starter Tray. Using a reservoir below the cells and a self-watering mat, this model ensures that your seedlings will always be evenly watered, taking a bit of the headache and babysitting out of the germination process. We found that 100% of the cells produced sprouts during our seed-starting experimental phase, making the Burpee Self Watering Tray a solid choice for beginners. As with the other Burpee models we've reviewed, this kit includes coconut fiber pellets.

Similar to other Burpee models, the pellets are a bit time-consuming and somewhat of a hassle. This may be a fun project for kids, but if you want to germinate several trays at once or plan on using your starter kit for professional applications, this may not be the best choice. This kit is best for those who don't want to have to keep a close eye on proper watering.

Growing Medium: Variety | Dimensions: 7.75" x 5.25" x 3.5"

Perhaps you're in the market for a seed starter kit to be a permanent fixture in your home rather than something that gets used a few times a year. The Judith Bloom Self Watering Seedless Tray is ceramic and offers a much less intrusive look than some other kits that appear to belong in a laboratory rather than a home. This self-watering version uses a reservoir that is easily filled through a hole on the top of the tray. At only a bit more than five inches wide, the Judith Bloom easily fits on most windowsills, and it is easy to move around thanks to its ceramic composition.

Ceramic composition has its downsides — although it's sturdier than plastic, it can also shatter if dropped. The Judith Bloom Tray does not include a humidity dome, so you'll need to keep a close eye on your sprouts and seedlings in particular climates and weather conditions. Despite these drawbacks, we still love the look and simplicity of this model.

Growing Medium: Soil Pellets | Dimensions: 21" x 10.8" x 2.8"

Our favorite feature of the Jiffy SuperThrive Seed Starter is that it includes an upper tray that holds the soil pellets, which sits inside a lower tray for draining. This is particularly useful for instances in which your growing medium retains too much moisture because you can simply lift the upper tray out of the lower tray and dump out any excess water. We are fans of these types of soil pellets — they expand quickly, and then it's easy to plant your seeds.

The double-layer tray helps with sturdiness a little bit, but overall these trays are flimsy. Although we like that you can control the humidity a bit by draining water out of the lower tray, the humidity dome is missing vents. Compared to the other kits in our side-by-side analysis, the Jiffy SuperThrive Seed Starter showed a low sprouting percentage per tray. After eleven days in our temperature & humidity-controlled room, only 19 out of 50 seedlings appeared. This model may be best left to veterans or people prepared to babysit their trays for a week or two.

Why Trust GearLab

Our review process began by spending hours researching the top seed starter kits available before purchasing the most promising ones for various applications. We thoroughly inspected each model for special features, durability, and strength. We then constructed a miniature grow room using the same lights for every tray except for systems that had lights included.

Ross Patton, our In-House Review editor, has had his hands in the soil since childhood, helping his mother plant veggies in the backyard as soon as he was able to. He completed his Bachelor of Science at the University of Nevada, Reno, where he majored in Environmental Science. Focusing on the Eastern Sierra Nevada Mountains' flora, he completed courses such as soil chemistry, advanced plant identification, and climatology. In the professional world, he has consulted for well-known brands such as Full Circle Compost. Much like Ross, our In-House Senior Research Analyst Michelle Powell began gardening in her youth. Since joining us at GearLab, she has tested all types of home & garden products ranging from outdoor solar lights to indoor gardens to waffle makers. Their combined knowledge and experience make for a great team that will uncover even the tiniest of details that make a distinction between these products.

Analysis and Test Results

A good seed starter kit will help you grow a bag of seeds into as many baby plants that are ready to be transplanted as possible. They include accessories such as lights, humidity domes, and heat mats and can even be self-watering. Some would look right at home on your window sill, while others aren't exactly adding much feng shui to the room. They can be made out of durable plastic, thin plastic, or ceramic material. Outlined below is an in-depth discussion of the various considerations we assessed and strengths we discovered during our hands-on testing process.

Growth

While reviewing seed starter kits, our team agreed that by far and away, the most crucial factor to consider was how many seeds grew to be seedlings in each tray and how healthy the plants were in an actual side-by-side environment. To test each of these home gardening products' growing performance, we set every kit up in the same room to remove any variability in temperature or humidity. We used the same lights for each kit except for the models that included their own lights. We then planted a variety of seeds in each slot and tracked their progress over the course of two weeks.

During this assessment, it was clear that the Super Sprouter Premium Heated Propagation Kit outperformed the rest. Not only was there a 100% germination rate, but the seedlings in this tray grew faster than the rest. By the end of two weeks, the tiny plants looked much happier than the seedlings in other trays and were, without a doubt, ready to transplant to pots or garden beds. The Burpee Seed Starter Tray showed admirable results after two weeks. Every seed sprouted, but they were not quite thriving like the babies grown in the Super Sprouter. Another product that showed promising results for this experiment was the Window Garden Seed Starting Kit. 100% of the seeds sprouted, but they were slightly smaller than the sprouts in the Burpee Seed Starter Tray.

Features

If you're an avid gardener, you may be looking for all of the bells & whistles. On the other hand, if you're looking for a kit that's a little more decorative than functional, you may be seeking simplicity while searching for the right seed starter system. Some people may want a kit that includes a growing medium, while others may want to choose their own or prefer a certain type of medium that's worked before. A few of these products come with heat mats or even lights to make the whole seed propagation process as easy as possible. We dedicated this portion of our analysis to the features and accessories included with each kit.

The clear champion of this section of our review is the Super Sprouter Premium Heated Propagation Kit. This kit includes a heat mat and a light that fits on top of the dome — two components that are often sold separately. This model has humidity vents to help fine-tune the micro-sized ecosystem for your seedlings. We love that the EarlyGrow Medium Domed Propagator includes an inner and outer tray to aid in draining excess water if need be, and this model has vents on its dome as well. The Burpee Seed Starter Tray is similar to the EarlyGrow in design, but unlike the two models mentioned above, it includes a growing medium in the form of soil pellets. The Window Garden Seed Starting Kit also includes soil pellets, and we love that this kit includes three sets of trays and domes.

Ease of Use

The primary purpose of a seed starter kit is to increase the chances of your babies sprouting and flourishing by being able to carefully monitor light, humidity, and temperatures indoors rather than putting them straight into a larger pot or directly into your garden beds or the ground. The idea is to make it as easy as possible to turn as many seeds into healthy plants as possible, so carefully consider the difficulty of using each one of these products.

We found the EarlyGrow Medium Domed Propagator to be among the easiest to operate. All you need to do is stick seeds in the growing medium, lift the lid to water, and dial the vents to adjust humidity. The Window Garden Seed Starting Kit is a bit more time-consuming to set up than the EarlyGrow because you have to wait for the pellets to expand before planting. However, when it comes to transplanting your seedlings to a bigger pot, the Window Garden Seed Starting Kit is the easiest to move around. A bit more complicated, the Super Sprouter takes a few extra seconds to get going because you have to deal with positioning the heat mat underneath the tray, and each time you lift the dome, you have to be conscious of the light and its cord. Finally, the Burpee Seed Starter Tray takes the longest to get planting because you have to soak and then physically break up the included soil pellets by hand.

Durability

Whether you'll be reusing your starter kit time and time again, or you're hard on gardening equipment, it'd be wise to consider these products' durability. The growing medium can often get heavy as it fills with root mass and water. The last thing you want is to pick up your tray full of babies that need to be moved or transplanted, only to have the whole thing fold or collapse. For this reason, we considered the durability of each kit.

If you're looking for a tray that will endure many rounds of germination, it's hard to beat the EarlyGrow Medium Domed Propagator — it was clearly built to last. We found the SuperSprouter to be reasonably strong. Although it can't match the EarlyGrow, its construction and components are much more durable than many of the kits we've seen. If you're not concerned about durability or you only plan on using your system for a run or two, the Burpee Seed Starter Tray and Window Garden Seed Starting Kit will do just fine.

Conclusion

Growing plants can be a fun hobby, a great learning experience, and a way to produce food for your family, friends, and community. Starting them from seed rather than buying your plants from the nursery is especially satisfying. Getting an early start on your garden from the comfort of your own home during cold winter nights can make a big difference in the quality of your garden when it comes time for flowers to bloom or veggies to be eaten. We enjoyed creating this review, and we hope that you now have the knowledge to choose the ideal kit for your budget and needs.