Saturday, June 11, 2011

Potato Blossoms and Bindweed

potato blossom with bonus field bindweed

The potatoes that Charlie planted back in February are starting to bloom. I think these are the fingerlings, but I don't know for certain because someone neglected to make up labels as they were planting. ::cough, cough, Charlie, cough::

We used the potatoes that we grew last year that somehow escaped being eaten for dinner and sprouted quietly in a corner of the basement.

These were planted in a trench and then hilled two or three times as the vines grew up. We'll harvest the potatoes once they're done flowering and the vines start to die back.

At one point I was concerned that the vines were developing a blight because the leaves looked singed and crispy, but the vines bounced right back and look nice and healthy now so, in retrospect, I think it was just the really unseasonably cold weather we had this spring.

The field bindweed* that you see amongst the potatoes is a real problem in our area and the end of the garden where the potatoes are this year has the heaviest bindweed infestation. I plan to clear out this area after the potatoes are harvested and work on eradicating this weed with some focused weeding and root removal followed by a late summer/early fall application of RoundUp.

Field Bindweed (Convolvulus arvensis)

We usually rely on persistent manual weeding and root removal to clear out an area (which is exactly how we cleared out the huge patch of ivy in the back yard after we bought this house), however bindweed is very challenging to clear out this way and even if one is really dedicated it only provides limited (and usually temporary) success. Missing just a couple of bits of vine allows the roots to quickly regrow and a single, tiny piece of root will rapidly produce miles of vine that quickly overwhelm other plants, being nearly impossible to remove without damage to the desirable plant.

Field bindweed in perennial fuchsia

So just how difficult is field bindweed to control?
Here's an excerpt from the link about field bindweed above:
In its first year it can grow from seed into a plant with a root system five feet deep and ten feet in diameter with many plant shoots. Each plant will store nutrients in the root system that can reach depths of greater than fifteen feet and will grow new plants wherever the root is broken.

Each plant can produce as many as 500 seeds that can sprout for over 5o years.
(emphasis is mine)

That's why I like to combine manual removal (to weaken root reserves) with a carefully timed, light application of RoundUp. RoundUp gives really good results if used in the late summer or fall when the plant is storing energy and nutrients back down to the roots. If applied earlier in the season, the plant is growing from the root and will quickly recover from the initial die-back, requiring multiple applications. My goal is to kill the bindweed while using as little chemical spray as possible.

* also often referred to as morning glory, wild morning glory, European bindweed or creeping jenny

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