Trays + Domes

Why Use Propagation Trays and Humidity Domes?

Seedling trays and humidity domes are designed to keep moisture and warmth where your young plants need them most. The tray holds your starter plugs, rockwool, or seedling mix while the dome locks in humidity to prevent cuttings and sprouts from drying out. This controlled environment reduces transplant shock, improves germination rates, and supports stronger early root development. With better consistency across every cell, you get uniform, healthy starts ready to move into your hydroponic system or soil beds.

Types of Trays and Domes for Every Grow

There are many options to match your style of propagation. Standard 10"x20" seedling trays are perfect for inserts, plug trays, and starter cubes. Heavy-duty trays offer extra rigidity for frequent handling and large-scale projects, especially when combined with wire shelving or multi-tier racks. Vented humidity domes let you fine-tune airflow and moisture, while tall domes give extra room for leafy cuttings and faster-growing seedlings. Together, these propagation trays and domes create a flexible platform for seed starting, rooting cuttings, and raising young plants for any indoor garden or hydroponic setup.

How Trays and Domes Help Hydroponic Growers

For hydroponic growers, uniform starts are essential. Using a seedling tray with a matching humidity dome helps you root cuttings and sprout seeds in a clean, organized way before moving them into deep water culture, NFT channels, ebb and flow tables, or other systems. Stable humidity between 60–100% keeps tender foliage from wilting, while steady temperatures between 75–85°F support rapid root initiation. This early control saves time, reduces losses, and helps every site in your system fill with a strong, healthy plant. From herbs and leafy greens to fruiting crops, a reliable tray-and-dome combo is the foundation of a productive grow room.

Frequently Asked Questions

Are seed trays worth it?

Yes. Seed trays help you use space efficiently, keep your growing medium contained, and make it easier to water, label, and move young plants. They promote even spacing and better airflow around seedlings, which supports stronger stems and healthier roots. By reducing waste, organizing your starts, and improving germination uniformity, seed trays usually pay for themselves quickly in saved time and higher success rates.

Are humidity domes necessary?

Humidity domes are not absolutely required, but they are highly recommended for most indoor propagation, especially in dry or air-conditioned rooms. A dome helps maintain the 60–100% relative humidity that seedlings and cuttings love, reducing wilting and moisture stress. While experienced growers can sometimes manage without domes, using one makes it much easier to keep conditions stable and achieve consistent rooting.

How long do I leave the humidity dome on my seedlings?

In many cases, the dome stays on for about 5–10 days, or until most seedlings have emerged and started forming their first true leaves. For cuttings, leave the dome in place until you see clear signs of new growth and a developing root system. Then gradually acclimate plants by opening vents or propping the dome open for longer periods each day before removing it completely. Leaving the dome on too long without venting can encourage mold and damping-off, so a slow, controlled transition is key.

Should I put water in the bottom of my seedling tray?

You can add a small amount of water to the bottom of your seedling tray to bottom-water and let the cells or plugs wick up moisture. This helps encourage deeper root growth and keeps foliage dry. However, avoid keeping a large amount of standing water in the tray for long periods, as overly saturated media can suffocate roots and invite disease. Allow the medium to nearly dry between waterings, and always follow the specific recommendations for your plugs or mix.

Is a seedling tray necessary?

A seedling tray is not strictly necessary, but it makes propagation far more organized and efficient. Trays are designed to fit standard humidity domes, heat mats, and shelving, so you can scale up easily and keep your grow area tidy. Improvised containers often waste space, make watering messy, and do not pair well with domes or racks. Using proper propagation trays improves consistency and simplifies every step from sowing to transplant.