Setting out biodegradable plastic mulch by hand

Pulling the roll of biodegradable mulch. Credit Wren Vile
Unrolling the biodegradable mulch and setting it out by hand.
Credit Wren Vile

Last week I wrote about the chemistry of various biodegradable plastic mulches, and how much we like using them. I promised to write about how we go about setting the mulch out without using tractors or mulching machines. We use maybe 8,000-9,000 feet each year, so we buy whole rolls, one at a time.

Pulling the biomulch roll using the special hand-made tool. Credit Wren Vile

The first year we used the biodegradable plastic mulch, we had two people pushing the roll over the ground, as others shoveled soil onto the edges behind them. It was a bit of an Olympic sport, so we had to be in the right mood. If we saw it as a challenge, we did well. Then one of the crew invented a simple tool, a stick that goes inside the roll and has rope attached, so the roll can be pulled by one person, standing upright. Much better than bending to push a roll on the ground! A snag was that the rope would sometimes get twisted up with the stick. This year’s refinement of the tool is to have the rope attached to the ends of the stick with swivel clips. This allows us to unclip to take the roll off the stick, rather than use our teeth to untie the knotted rope!  We’ve also added a length of bicycle inner tube over the rope as a more comfortable handle.

Following closely behind the person pulling the roll we have two energetic “Forward Shovelers” whose job is to get a shovelful of soil on each edge of the plastic about every yard. We don’t want the Puller to get too far ahead, especially if it’s breezy! We want to “tack” the mulch safely down on the ground. Here we are mulching for sweet potatoes, so we have ridged the soil and run out drip-tape.

The Forward Shovelers follow close behind the person unrolling the plastic. Credit Wren VIle

Behind the Forward Shovelers are the Rear Shovelers, usually at least four of them. This day, one was taking the photos, and others have mysteriously disappeared into the shade, so we don’t really have a good photo of this part.

About four Rear Shovelers complete the team. Here they are in the distance. Credit Wren Vile
About four Rear Shovelers complete the team. Here they are in the distance. Credit Wren Vile


A Rear Shoveler completes the line of soil holding down the edge of the biodegradable mulch. Credit Wren VIle
A Rear Shoveler completes the line of soil holding down the edges of the biodegradable mulch. Credit Wren VIle

It is possible to successfully store a roll of biodegradable mulch from one year to the next. The keys to success are to carefully wrap the plastic to exclude light, and store the roll on end, fairly vertical. If laid flat, the layers of plastic could stick to each other and not be rollable. Of course, you also need to keep mice away, and protect the roll from sharp implements. So if you need 4,00 feet per year, you could buy a roll every other year. This is generally a better deal than buying short lengths. As I said last week, I buy from Nolt’s Produce Supplies in Leola, PA (717) 656-9764. They sell Bio360 BTB645 4′ x 5000′ for $345 plus shipping, and Eco-One E1B548 4′ x 8000′ for $243 plus shipping. They don’t use email or websites, and they’re closed on major Christian holidays, so don’t call then! Johnny’s Seeds sells 32′ lengths for $17.95. Robert Marvel sells whole rolls of Eco-One and Bio360 (call for prices).

So this week, our mornings have been spent laying drip tape and rolling mulch, and our late afternoons transplanting. We have done really well this week, and we’ve transplanted all our watermelons and sweet potatoes. This brings to an end our intensive spring transplanting. Now we just have the leeks, the weekly planting of 120 lettuces, and a check on all the existing transplants about a week after planting, to replace casualties. We’ve also got all our T-posts in for our Roma paste tomatoes and started our string-weaving.

Peak Watermelon Day?

This morning we picked 99 watermelons. I hope this is the peak day of harvest! We’ve been harvesting on Monday and Thursday each week since 7/30 or maybe 7/26, I’ve already forgotten! Numbers have leapt up: 10, 34, 37, 99. We need 22 melons a day during hot weather, to keep 100 people happy. So for all of August, September and a few days of October, we need 700-800.

But today’s 99 is not our all-time record. In 2010 we picked 120 on 7/31. And in 2008 we picked 320 on 8/20. That was too many and too late in the year. I’ve only got records back to 2000.

2000 was a bad watermelon year. We used to transplant into hay mulch, for weed control. Of course, we knew hay would cool the soil, and watermelons love heat. But we just couldn’t deal with the weeds any other way. We hadn’t started using drip tape irrigation back then, so our overhead sprinklers watered all the weed seeds in the aisles between the rows too. We used a vast space, with 10′ between the rows. We didn’t get ripe melons till well into August. 2001 wasn’t much better.

In 2002 I did some research into plant spacing and found we didn’t need to give the plants (and weeds) so much space. So we cut the row spacing down to 5.5′ and planted twice as many melons. 5.5′ is just the right width for unrolling big round hay bales between the rows. We started harvesting 8/3. Much better! We got 60/week in the middle of August and 100/week by the end of August. Still peaking much later than sensible. Watermelon in October is like yesterday’s newspapers – there’s not much demand.

2003 had a wet spring, we planted into mud. The harvest peaked 9/16. In 2004 transplanting dragged out. Our new rowcover had a manufacturing defect and disintegrated like wet toilet paper all over the field. We got our money back but the plants were set back by the lack of cover when they needed it. We started saving our own seed that summer, selecting for early ripening and good flavor. Also presumably for spring cold-hardiness as they were from plants that didn’t die.

In 2005 I did more research into spacing, and we planted 2.5′ apart in our 5.5′ rows. It seemed wiser to plant closer and go for more plants and so more first melons (one on each plant), as it is early ones that we want. Keeping geriatric vines alive to produce a third melon or so seemed to be missing the whole point of eating watermelon in hot weather.

At this point in our history, we were still harvesting up until frost (average mid-October here). We were planting about 1260′. We started to track how many melons we had on hand and what rate we were consuming them, so we could decide when we had enough and stop picking.

In 2008 we had no hay mulch available. From this disaster came a wonderful thing: we discovered biodegradable plastic mulch. We have used two brands: Eco-One Oxo-Biodegradable mulch  (made in Canada) and Bio-telo (made in Italy). This product is made from non-GMO corn and it starts to disintegrate after a couple of months in the field. It’s very thin and easily torn if the soil underneath is not smooth. It’s perfect for vining crops, because it stops the weeds growing and doesn’t disintegrate much until after the vines cover the whole area. And the big plus is that the bio-mulch warms the soil, rather than cooling it. Biodegradable mulches are now available in smaller pieces for backyard growers, from Johnnys Selected Seeds and Purple Mountain Organics.

We planted 1800′,  more than usual because the area the rotation brought them to was a bowl shaped garden where crops sometimes drown in wet years. We started harvesting 7/31, and numbers rose rapidly.We didn’t get any floods.  By 8/20 we had harvested 1000. That was the year we decided not to wait for frost, but to disk the patch in early and get a good cover crops established for the winter.

2009 had a peak harvest of 174 on 8/15. I think we stopped at 835 total on 9/2. 2010 records show an early start with 2 harvested on 7/18. We stopped at 665 on 9/8. We tried to experiment with various row spacings and plant spacings, but once the vines all meshed together and the weather got hot, our enthusiasm for science waned! We were planting 1060′. August had an inhuman workload, and we decided to see what we could do to reduce August tasks for future years.

In 2011 we decided to plant less, as were short of workers. We planned on 1080′ but then cut back further, and only planted 900′. This year we only planted 800′, with plants 36″ apart, so a lot fewer plants than in the old days of 1800′ and 30″ spacing. The melons are huge this year – I bet we don’t eat 22 of these a day!

So, having looked at the numbers here in the relatively cool office, I deduce that we haven’t picked anything like enough yet, and need 5 more 99-harvest days before we think about quitting. Time to start using the truck rather than the garden carts, for hauling them away. We’ve found the hard way that even though we can get 20 or so melons in a garden cart, it damages the carts and wrecks the tires. So now we keep to a 16-watermelon limit and save the carts.