A Season's Knowledge

I think it is late enough in the growing season to make some sound judgements regarding my vegetable planting boxes. First -they worked. They held together, held the soil, supported the plants, even did not dry out too fast.

• For green beans, the box worked out excellent. Ten to twelve inches wide and the same in depth, I was able to get an amazing amount of bush beans in a small planter. The longer the box, the more plants. I planted mine with two parallel rows down the length of the planter. A great success.

• My 12 x 12 x 12 parsley box has worked quite well too. Similar sizes work great for basil.

I have a varying sizes for the tomatoes and this is where my critical judgement comes in.

• Twelve by twelve by fourteen inches deep is not enough soil space for a rapidly growing large tomato plant like the San Marzano, Brandywine, or German Stripe I planted. These plants have meaty stems and grew 5 feet tall in one month's time. The plant's roots went through the planter bottom and tapped the ground. If you are growing on a rooftop, or concrete pad, or wherever, the roots may not be able to do this and the large plants will suffer during hot, droughty periods. They may also succumb to disease due to stress or become stunted.So my judgement is that large tomatoes, like those indeterminate heirloom types, require larger, deeper boxes. What depth? I can only guess at this point to say at least 20 inches, maybe 24 inches deep. The depth seems to be more crucial than the width.

• Smaller tomatoes, like cherries, grapes, and anything labeled "Patio" should do fine with 14-16 inches of depth. But stay on top of the watering. These boxes dry out sooner than the earth and the bushy plants shed water around them, not into the planting box.

My planting was very dense, 7 tomatoes in less than 40 square feet. The more room you can give them, the better for air circulation and light penetration.

I had some questions about whether or not to line the box with plastic. I do not do this anymore because I do not want to grow in plastic. I prefer to have the soil hold the moisture, then let it drain out. The plastic may prolong the life of the wood planter on the interior. But I don't think it is a significant increase in life of the planter to warrant it. However, the plastic may increase resistance to blossom-end rot and cracking of tomatoes by maintaining a steadier moisture level. So this is a matter of personal choice, although you do want to be sure there is some drainage in your planter. Over wet soil is as bad for plants as drought.

For a reason that has remained a mystery all season, my cilantro has been sickly. I think this is because the soil has remained wet no matter what the weather conditions. I do not understand this, there is drainage in the planter (is it clogged?). Not until I empty the planter will I find out.