Row Cover and Low Tunnels for the Greens

Our garden has been periodically (and in some seasons, relentlessly) attacked by a wee little bug called a leafminer, going back to the rental, going back years.  While we may have hoped that moving across town four years ago would have changed the tide that proved not to be the case.  Our first year gardening at the new house our greens got gobbled up--or we spent our time manually removing the eggs (since we don't use sprays in our garden).  Matt did a little research and purchased a roll of row cover through an greenhouse supply company and decided to give that a try that as a deterrent.   It made sense.  Rather than kill the little buggers after the fact, why not just try to prevent them from taking up residence at all?

Row cover is a lightweight, white cloth which lets almost all the sunlight and water in, but which keeps bugs off the plants inside.  Matt made some hoops--out of wire, PVC, and irrigation tubing, all of which work and have their pros and cons--and transformed our raised beds of greens into little covered wagons.  Okay, not really, but they do look a bit like that.  Wooden boxes with white hooped cloth covers stretched over top.

It works magnificently.  We had, quite literally, no leaf miners on the plants inside the low tunnel of row cover.  I had a little test plot of spinach just five feet away that was quickly infested with leafminers.  We were immediately convinced.

The only negative, in my opinion, is aesthetic.  Exposed, open plants looks more attractive to me than beds with low tunnels over them.  Still, exposed, open plants look more attractive to pests like leaf miners, too, apparently.  I can't really blame them.  For me, its well worth it to sacrifice a little in the way of aesthetics in the interest of not having to deal with leafminers anymore.  Also, I suppose they may not work well with crops that need to be pollinated by flying insects.  I am not certain about that from my experience as most of it has been with leafy greens and other non-flowering veg.

This will be our third year using the low tunnels. We've made some refinements as we've had more experience using them.  We laid a long board next to each side of the beds which we use to pin down the edges of the row cover, making a tight seal with the ground.  By stapling the edge of the row cover to the board we were able to use it as a handle so we can more easily cover and uncover the bed in one motion when we need to harvest or thin.  That was a good innovation.

After the success with the leafy greens the first year we started using the low tunnels over additional crops in the following year.  Cabbage is another vegetable that frequently attracts unwanted insect pests and the covering works well at discouraging cabbage moths, too.

The row cover offers just a couple of degrees of protection against frost, too.  This is nice in the early season when we still get the occasional snow.  Spinach are tough and can handle it, but the extra layer of protection sure doesn't hurt.  Later in the year, we take the row cover off when we replace the early, cool-weather crops with a second wave of warm weather crops.  Even still the low tunnel set-up can come in handy.  We take the row cover off, but leave the skeleton frame of hoops as is.  In this way we can quickly and easily cover the peppers or eggplants against the early frosts of autumn.

Its definitely a practice we will continue to employ in our garden.  Its effective, simple, non-chemical, low-maintenance, and multipurpose.  There was some upfront cost in purchasing the roll of row cover and the hoop materials, but the hoops are good now for a decade or more, I'd bet, and I suspect this row cover will hold up well to reuse, too, at least for a few seasons, depending on weather.  They don't hold up to hail, we have learned.  Oh well, nothing last forever...

We'd totally recommend low tunnels of row cover for pest prevention.