Grodan A-OK 1.5" Rockwool Starter Plugs – 2 Half Sheets of 49 (Total 98 Plugs) – Made in The Netherlands – Includes Twin Canaries Chart

Since watercress is a semi aquatic plant, I bought these Rockwool Starter Plugs to grow watercress by partially submerging them in clay pebbles kept in water. After I soaked the Rockwool plugs, I buried them almost half way into the clay pebbles which were kept almost entirely covered in water. The container holding the plugs and pebbles had holes drilled in it, and this container was placed in another that held the water.From what I can see, I got 100% germination of the watercress seeds, and they seem to be happily growing so far as you can see in my pictures. Although I believe any seeds would germinate on these starter plugs, you may want to choose a different growing medium if you are growing plants that you want to separate later or plants that you want to grow outside. With this growing medium, it would be difficult to separate plants without losing some of the roots which would be detrimental for the plants. If you want to separate plants, it would be better to choose a growing medium that will allow you to easily lift out the plants with little to no damage to the roots of the plants.UPDATE 07/11/19:Using these Rockwool plugs for my watercress, the plants have doubled in size in a week. The 3rd and 4th pictures were taken one week after the first two pictures. By burying the plugs half way into the pebbles that are kept under water, the plugs are kept constantly moist and my watercress looks very happy.UPDATE 08/04/19:The 6th picture was taken about 3 weeks after the 5th picture, and I have already harvested enough for 3 salads 5 times. This watercress is growing almost faster then we can use it.UPDATE 9/23/20:For those of you who want to grow watercress that will regenerate indefinitely foe a constant supply of this healthy green, I have finally found a method that really works and the watercress continues to grow faster than you can use it.In it's wild habitat, watercress grows at the sides of rivers in a bed of gravel. This area is kept relatively wet and the water is almost constantly flowing. The water is high in nitrogen from plant and fish wastes which feeds the watercress. This keeps the plants and the roots of the plants healthy. I have watched a number of videos on YouTube showing watercress grown hydroponically, in pods does not allow for the natural growth of watercress as it spreads with roots that grow from the stems. Since the plants reproduce and grow by new stems rooting, these methods are for very short term production. Within a couple of months, the roots of the plants rot and the plants die.Using this information, I decided to try growing watercress in a grow bowl I had for for my AeroGarden. I filled the grow bowl with saturated clay pebbles, filled the grow bowl with a hydroponics nitrogen plant food at half strength, set the pump to run for 2 minutes every 2 hours, and sprinkled the watercress seeds on top of the stones. After the watercress was growing well, at about 4 weeks, I set the pump to run for 2 minutes every 4 hours. I keep the water level up in the reservoir, and change the water ever 4 weeks with a new solution of water and plant food at full strength.I have added a picture of my watercress crop that has been growing for about 4 months with no yellowing leaves and no root rot. I have already harvested enough for meal veggies or 3, have given away gallon baggies of it a couple of time, and use it twice a week for salads for 3. It is still growing faster than I can use it. Each time it has grown back to where it was within a couple of days. Although the other methods of growing watercress mentioned in the review work, they provide short term crops. This is the only method I have found so far that provides a long-term continuous supply.I hope this review was helpful for you.

I was having trouble growing my seedlings in dirt they kept dying. So far these rockwool cubes are great my trees are doing great I don't need to water them everyday.

Super high quality.Buying again

Worked like you'd imagine nothing special but great item. For it's purpose

Product comes as advertised. Great value for the price.

Love it

I recently tried these rock wool cubes, and while they did work, they weren’t quite what I expected. The texture felt different from the usual rock wool I’ve used in the past. It was much denser and didn’t have that typical “whispy” feel. This made it a bit harder to work with, especially when creating the opening for the seed. The hole was really small, and I had to use a bit of force to make it large enough for the seed to fit comfortably.Additionally, I noticed that the water didn’t absorb as well as it does with the usual rock wool. Instead of soaking in, it kind of just ran off the surface, which was a bit frustrating. I had to keep an eye on the watering more than I usually would to make sure the cubes stayed moist enough.While the cubes did eventually work for my plants, the differences in texture and water retention made the process a bit more challenging. They might be fine for certain setups, but I personally prefer the more standard rock wool for its better water retention and easier handling.

I wanted to work with materials that were far more sustainable than plastic. I had just begun working with aeroponics and hydroponics and these Rockwool cubes, vermiculite, and coco coir cups are going to be the perfect combo to hold and sustain the garden I’m making.Be careful to not oversoak it because it sometimes becomes a little difficult to tear apart