When working with rockwool in the Towergarden. It’s possible to run into this:
I had had my entire tower with organic strawberry seedlings.
It’s a risk to take seedlings from a supplier and plant them in the Tower for a couple of reasons. First, the plants are introducing foreign materials, such as insects, to the garden and the natural growing environment of the garden, which can introduce more issues of a very varied sort. It’s easier for the gardener to protect the seedlings when in control of the whole lifecycle of the plant/seed. When our crop becomes our food, it is important to have the highest quality. Second, it’s a risk to use seedlings that we’re grown in soil and then transfer them to the tower. The tower is best used by growing the seedlings directly in the rockwool medium, for likely reasons seen in the picture above. The nutrient content that is added to the water is the perfect mineralization for our little growing seedlings. I’ve never seen plants grow so quickly like they do in my tower, in all my experiences, even in this case where an algae problem arose.
So, fortunately there were no prior problems, but this is quite a mess now. The reason behind the choice of using the soil grown seedlings from another supplier was simply a matter of saving time. In the past this worked wonders for my schedule. However, after emptying and scrubbing everything, I’m not sure if I will try again, or if I will wait until I have more time. I did get to enjoy some strawberries before the algae kicked in; and I love this tower so much, that it’s quite worth it to keep it going for my food needs. Sure, I already eat a healthy diet from the grocery store and farmer’s market produce. In the past I benefited from CSAs. But this tower is a learning experience that is well worth it over time. Can’t wait to see what we think of next, or what shows up to help us decide what to grow. I did read about a solution, from Hightimes: There are little caps that can be bought to add to the tops to keep the light out of the growing surface area, which supports the algae growth. Now, since I didn’t have this problem with any of my other plants (and plenty of light!), I’m wondering if the algae like the lower pH (more acidic) like the strawberries like. We shall see! Happy growing!