By far the best way to keep pest problems with broccoli under control in southwest Idaho, is to plant it in early April. If it matures before time periods of prolonged heat, usually beginning in July, you may not ever even see an aphid or cabbage moth on it. If you want larger heads or a longer harvest time, though, you will have to grow a variety that takes more time to produce. If you are willing to take a few measures, you may end up with a bountiful fall harvest as well, like I did last year.
Last year I had 2-3 different kinds of broccoli in 3 different places. The early row of plants came and went without much to show for my effort. We probably got 2-3 meals worth out of them. There were 2 later varieties so that I could experiment with using a fabric insect barrier, such as those you can find at Territorial Seed Company in the “season extenders” category. I found similar fabric at D&B Supply.
When the bug hordes started to arrive, I sprayed 1 row hard with water, to remove the bugs. Then, I covered it with the fabric barrier, using the suggested fabric staples to secure it. (These can also be found at D&B Supply) The OTHER row of broccoli, I left open to the air and sprayed with insecticidal soap on 2 separate occasions during the height of the infestation.
The broccoli plants under the fabric continued to grow, but always seemed a little scrawny compared to the open air row. This could have been because of what variety it was. Unfortunately, I don’t remember if it was a distinct variety or the name.
What I DO know is that using the staples to secure the fabric made it very difficult to check on the plants, for anything from insects to impending harvest. If I use the fabric again, I will have at least one edge attached to some boards or sticks that are easy to pick up and replace. The staples were hard to locate in the dirt, then hard on my hands to push back in. It made me not want to attend to the plants. Another strange phenomena was that the breeze would catch the fabric, since placing the fabric staples any closer than 2 feet apart was tedious on many counts. The cabbage moths found their way in with the wind, but couldn’t find their way out! It was an excellent way to catch meals for the lizards, but not what I was hoping for for the broccoli. 🙂 The harvest was rather pitiful.
In August, the OTHER row of broccoli began giving me bowls and bowls full of good sized secondary heads that we were harvesting until October. This variety is Arcadia from Johhny’s Selected Seeds, a company I have ordered from for over 20 years. I have grown this hybrid broccoli a number of times, but have never been as thorough about spraying with insecticidal soap. Also, as any gardener knows, the weather in any given year can have a great deal to do with how a crop turns out.
I am trying Aracadi(F1) again this year for my longer season broccoli. I am still deciding about the fabric row cover. It certainly won’t help against the ants that have come back to torment me in my early season crop.
Diatomaceous earth doesn’t seem to be slowing them down much, but I didn’t completely thin the seedlings, hoping that this would be time limited as it has been in the past. Some for them, some for me… They seem to leave it alone after it gets thicker and stalkier. Or maybe I’ll get some lizards that eat ants. I’ve seen pictures of these from my kids on their adventures with their dad in the local sagebrush. Either way, the broccoli is planted and spring is full of hope for this year’s harvest! What do you do for pest control on broccoli?