Finally we're getting some summer heat. Now that it's been cool and wet all summer it's into the nineties and humid; to say that we're not used to it is an understatement! Great growing weather and even better for killing weeds. Here's a good subject for today - what you do now will make life easier next year. And with everyone picking beans and harvesting other fruits interest in weeding is definitely waning but............
Weeds are survivors. How many weeds do you see dry up and die in the heat and droughtlike conditions of summer - none, that's how many. They haven't been bred to need TLC like so many of our vegetables we eat. They survived long before modern agriculture and have only thrived and become stronger by us feeding them. Weeds are one of the biggest challenges facing growers be they gardeners with a home garden or farmers with acres and acres. Identifying them and knowing their life cycle can greatly improve your control of them. Some weeds are sensitive to frost, some can be controlled with black plastic and some cannot. Some live in the soil as seeds for fifty years and some will be gone in a few. Some like fertile soil, some prefer poor and compacted soil. Many weeds will disappear if their home soils are altered by fertility or cultivation.
Weeds are setting seed now furiously to ripen ahead of fall frosts. The Hairy Galinsoga is blossoming like crazy and growing new plants from seed sprouted now. Galinsoga needs no dormant spell, so it will germinate and set seed up until frost. Whereas the spring and early summer Galinsoga plants will be as big as a bushel basket if unmanaged, the seedlings that come up now will be small and they go right to seed shortly after germination occurs. Galinsoga is called "quickweed" in some places and this is why; several overlapping generations per year are possible. Most weed seed needs a certain amount of time after blossoming to set seed and mature - not Galinsoga. Once it blossoms, the seed is mature and ready to grow. Normal weeds, if pulled out and left in the sun to dry, will not have mature seeds and can't make them. Galinsoga can. If you pull galisoga in bloom and do not remove it from the garden, you might as well not have pulled it at all. And, unless you have a hot compost pile, don't toss it in the compost pile. Toss it on the burn pile or into the woods. As you can tell galinsoga is my least favorite weed. Perhaps fifteen years ago we had a small patch in one field, now we have it in nearly every field we rent or own; a total of around eighty acres. Left unchecked it will overtake fields and choke out the very plants you're trying to grow. If you don't get to pull the tiny plants you're probably best off to get the ones going to seed; make it a goal to get all the weeds going to seed and you'll have thousands and perhaps millions less seeds next year to deal with.
Redroot pigweed and lambsquarters tends to put out large amount of seeds as well as the galinsoga. These, left unchecked, can produce between 400,000 and a million seeds per plant. A million seeds- that's a bunch; I think the average is less than that, but still a healthy amount of seed. Both of these species need time to mature seed after blooming. Once the seed in the seed head turns black, it is mature and will grow if giving the optimum conditions, like heat and sun next spring. As long as the plants are pulled before the seed becomes mature, they can be left on the surface of the garden to die, dry and become the ever important organic matter. If the weeds are really large and will pull up a garden plant when pulled out, they can be cut off with pruners just beneath the soil surface. As a rule they won't regrow.
Whilst writing this it occurs to me that not everyone knows how to pull weeds. There's a right way and a wrong way (yes, there's a wrong way to pull weeds). If weeds are pulled up by the roots (not broken off) the soil shaken off and put in a place where they can't reroot, they'll die. As an example two weeders in the tomato patch last week - one pulled them and tossed them in the middle aisles; the other pulled them up, shook the soil off the roots and tossed the weeds on the plastic between the plants. The first weeder was far faster than the second one. Which look better today? The second weeders weeds are dead; the first weeders weeds need to be pulled up again, a complete waste of time. The weeds were perhaps slowed down for a day or two but, with the soil still on their roots, rerooted and continue to grow with the ultimate goal of setting seed. The first weeds dried out in the sun in a matter of a couple of hours; they didn't have a second chance.
All weeds will die on a hot summer day if pulled in the manner described above with one exception - purslane. Purslane is a succulent which holds water in its stems. If purslane is pulled out, flipped over and left on the plastic to die, it will simply continue to grow, flower and set seed. There's only a couple of sure fire ways to kill purslane: you can eat it, feed it to the chickens or compost it. When small it can be killed by burying it; we do that with the cultivators. Otherwise removing it from the garden is the only option left.
Other weeds of interest are some of the easiest to kill but often overlooked ones: Velvet leaf, Prickly Lettuce, chickweed in the understory of crops, field bindweed and crabgrass. This late in the season, many weeds will go unnoticed in the understory of mature garden plants. Chickweed will thrive in the cool, shaded areas under garden plants. Bindweed will snake along throughout the crops hardly noticeable. Crabgrass will creep in on the edges of the garden, barely noticeable but spreading through roots and seed as well. Lastly we have Prickly lettuce and Velvetleaf - the easiest weeds to control. Pull them out or cut them off and they're done. That's kind of a bonus after pulling out galinsoga.
Until next week, Brian.