Understanding Seed Trays: My Favorite Seed Starting ...

If you are exploring the world of seed starting, you'll find that selecting the right seed tray is crucial. Seed trays keep your soil intact and support healthy transplants, making it easy to care for seedlings in a single container. According to a popular gardening resource, "The best seed trays are designed to promote drainage and support seedling health," emphasizing the importance of choosing wisely.

We can all agree that having various options is favorable, but sometimes, too many choices can leave us feeling overwhelmed. I certainly felt that way when I began growing flowers and was torn between different seed starting trays to buy.

No one wants to waste money on the wrong trays. Therefore, I aim to alleviate that concern in this blog. Together, we will examine the pros and cons of various seed trays available on the market. Additionally, I will share my preferred trays and key considerations to bear in mind while selecting your own.

Ready to dive in? Let's start!

Understanding Seed Trays:

Seed trays function primarily to keep your soil contained, ultimately enabling healthy seedling growth. By housing your seeds in a single tray, all your seedlings can be treated uniformly. This allows you to water the entire tray simultaneously and transport your seedlings effortlessly when planting time arrives.

Most seed trays have a standard length and width that fits into a bottom watering tray. However, the significant distinction lies in the number of cells each tray contains.

The Importance of Cell Size in Seed Starting Trays:

Tray cell counts can vary significantly, typically found in sizes ranging from 32-cells and 50-cells up to 128, 288, and beyond. The more cells in a tray, the smaller each individual cell becomes. For example, a 50-cell tray has larger cells compared to a 72-cell tray.

Your choice of cell count will depend on personal preference, available space for seed starting, and the specific needs of the seed varieties you are growing. The cell size dictates how much room a seedling has to develop; smaller cells can restrict growth.

It is essential to provide seedlings with adequate room for root expansion and top growth before they transition to the garden. When seedlings lack sufficient space, they may become root-bound, making it challenging for them to absorb necessary nutrients from the soil.

Although some seedlings may recover post root-binding, it’s typically better to prevent this problem entirely, as root-bound plants may face stunted growth or not survive at all. The goal of seed starting is to generate vigorous plant starts, so offering adequate space for growth is vital.

While maximizing space is imperative, especially on a larger scale, I’ve turned to wire shelves for growing my plants. Each shelf fits four trays and can house a total of 128 seedlings using 32-cell trays. Alternatively, if I use 72-cell trays, I can cultivate up to 288 seedlings on the same shelf, effectively doubling my capacity.

Best Seed Tray Recommendation for Flower Farmers:

My go-to choice is the 72 cell tray as it strikes a good balance between space optimization and seedling health. For most flower varieties, this cell count provides ample space for growth without the need for premature repotting.

Specifically, my favorite seed starting tray hails from Bootstrap Farmer. After five seasons, I can attest that I haven’t encountered a tray that matches its resilience and quality.

Even when fully loaded with soil, Bootstrap Farmer trays maintain their shape, proving to be remarkably durable. I consider the extra expense worthwhile, as these trays don’t require frequent replacements.

Let’s delve into scenarios where you might opt for alternative trays.

Seed Starting Trays for Specific Circumstances:

128-Cell (and Smaller) Seed Starting Tray

If you encounter difficulty germinating seeds, consider using tools like heat mats and humidity domes to create ideal conditions. However, when on a budget, you may not afford to equip every tray with these items.

Utilizing smaller-cell trays, like a 128-cell tray, allows you to maximize space while fitting comfortably on heat mats. Just be cautious about monitoring their growth, as you might need to transfer seedlings into larger trays for further development before planting them outdoors.

50-Cell Seed Starting Tray

For certain flower varieties, like sweet peas renowned for their extensive root systems, I always recommend a 50-cell tray. More recently, I’ve transitioned to using extra deep 50-cell trays to facilitate root growth.

We also use these deep trays for many crops, such as ranunculus and anemone corms, as well as potting up paperwhite bulbs.

That said, be aware that these deep trays can complicate moisture regulation. They may not effectively wick moisture from their drainage holes, causing me to rely on overhead watering rather than bottom watering.

20 Row Channel Tray

Another unique option is the 20 row channel tray, suitable for gardeners who find sowing small seeds tedious. For those suffering from eye strain when sowing tiny seeds like snapdragons or oregano, channel trays can be a game changer.

With this tray, fill each channel with soil, then create small indentations to pour seeds into. Typically, one seed packet fits nicely within a channel, saving considerable time when initiating seed germination.

Once the seeds germinate and seedlings grow, I transplant them into my preferred 72-cell trays for continued development.

Seed Trays We’re Trialing this Year:

Lastly, I’m excited to share a new tray I’m testing this season. While I previously focused on conventional trays, another method called soil blocking eliminates the need for a tray altogether.

Soil blocking prevents seedlings from becoming root-bound, as roots that reach the outer edge of the block encounter air, triggering air-pruning and encouraging secondary root development.

Despite these appealing advantages, I find soil blocking to be a bit finicky, which is why I prefer trays. However, I’m intrigued by air prune trays, which combine ease of use with the benefits of soil blocking.

These are an investment, but they are well-crafted, and I anticipate being able to utilize them for many seasons. I will keep you posted on their performance throughout the season.

Conclusion:

In conclusion, this post provides insights into various seed trays I utilize during the growing season. I hope it offers you considerations when deciding which trays to incorporate for flower starts.

Let me know your thoughts in the comments! I’m always interested in what gear other growers are using.

P.S. Want to see these trays in action? Don't miss this YouTube video showcasing my favorite seed starting trays!