Garden cleanup and soil improvement

Food gardens are in transition in October. Cool-season crops hit their stride and cover crops replace tired warm-season crops. Rather than put the entire garden to bed we may decide to coax more food from the ground with row covers, cold frames, and over-wintering crops. Either way, fall cleanup (“garden sanitation”) and soil protection and improvement this fall help ensure a healthy and productive garden next year.

Cleanup Tips:

  • Remove stakes, trellises, hoses, temporary fences, plant labels, and other gardening materials. 
  • Clean up and remove all above-ground plant residues. Many diseases can survive over the winter on small pieces of leaves and stems. Some pest insects will hunker down under protective layers of dead weeds and crop debris. Either bag up and dispose of these plant wastes or compost them. All parts of the bin or pile must heat up to >140⁰ F. to kill plant pathogens and weed seeds. (Japanese stiltgrass should be bagged up with regular trash for landfill disposal.)  
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Remove perennial weeds with a metal rake (ground ivy and grasses in this case).
  • Empty the growing media from container gardens and store it in a trash can or heavy-duty trash bags. Soil-less growing media and compost lose nutrients and break down physically over time. Mix last year’s growing media 50:50 with fresh growing media and/or compost next year. 

Soil Protection and Improvement Tips:

  • Instead of pulling plants out of the ground, cut them off at ground level leaving the root system intact. This reduces soil disturbance while adding organic matter.
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Partial root systems of eggplant at season’s end.
  • Don’t leave the soil bare. Cover it with shredded leaves or some other type of mulch to prevent erosion. Rake leaves into a loose pile and mow over them with a lawnmower to cut them up.  They will be much less likely to blow away if they are broken up. The leaves will reduce weed growth and can be retained as mulch next spring.
  • It’s getting late for planting cover crops. If you have seed, you can take a chance on sowing before the end of October. The soil temperature should be at least 45⁰ F. to 50⁰ F. for germination of cover crop seed. You can enter your zip code to learn the approximate temperature of soil in your area.  
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Bury plant-based food scraps in garden soil. This keeps them out of the landfill and recycles plant nutrients in the root zone. Unfenced gardens may attract wildlife.
  • As much as possible, use organic matter generated from your yard and household. Organic matter brought in from outside sources carries potential risks. Manure, straw, and hay may be contaminated with long-residual phenoxy herbicides or troublesome weed species. 
  • Invasive jumping worms have been appearing more frequently in gardens and landscapes. They are spread by the movement of soil and organic matter like mulches.
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Invasive jumping worm removed from a deep layer of garden leaf mulch.
  • Test your soil. For $15-$20 you can have an accredited lab test your soil. You’ll get some important baseline information on soil pH, nutrient levels, and organic matter. Lead testing is included with some basic soil tests (e.g., University of Delaware). Most vegetable and fruit crops grow best in 6.0 to 6.8 pH soils. If your pH is too high or too low some nutrients may become unavailable to plants, causing deficiency symptoms, or overly abundant, causing toxicity symptoms. If recommended by the lab, you can apply lime or sulfur to your soil this fall so they can start changing soil pH. 

By Jon Traunfeld, Extension Specialist. Read more posts by Jon.

Time to think about fall planting!

Wait… what?

It seems like you’ve just put that spring vegetable garden in… though actually, come to think of it, there are tomatoes reddening and squash burgeoning and summer is in full swing. But still, fall seems a long time away. Can’t we wait to think about it until it gets chilly again?

Well, if all you want to grow in the fall are lettuce and radishes, and maybe some spinach, sure. Given our tendency to long, warm autumns, you may be enjoying your summer vegetables well into October, or even November, if we don’t get a hard frost, so who needs to plant anything else? But those long autumns also mean we have an ideal situation for keeping our production going into winter. And if you planted broccoli or cabbage or cilantro this spring, or any other plant that prefers cool weather, and were disappointed when it went to flower early or began to taste bitter, let me tell you: fall is better. Temperatures that start a little warmer for tender seedlings and grow gradually cooler, resulting in frost-kissed sweetness and beautiful greens or root vegetables–terrific! You just need to do a little work to get there. Continue reading

The green tomato dilemma; or, will this fruit get any riper?

I was reminded on social media this morning of an article published back in June by John Porter on the Garden Professors blog. It’s about which fruits (some of which are vegetables in a culinary sense) continue to ripen after being harvested, and which don’t. Using more scientific words, which are climacteric and which are non-climacteric. There’s a useful list — bookmark it!

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Unripe Siberian kiwis in May

I referred to that list this summer to confirm that kiwis are among the fruits that will continue to ripen once picked. I have three Siberian kiwi plants (Actinidia kolomikta), two female and one male, and the females have been producing their tiny little fruits fairly bountifully. The problem with these kiwis, though, is that they don’t all ripen at once, and when they do ripen, the fruits tend to go from hard to soft quickly and then fall off. I’ve taken to checking the relative softness whenever I pass under the arbor during fruiting season, plucking off the ripe ones and popping them into my mouth.

So I thought, hm, what if I pick all the fruits once some have started ripening, and let them finish indoors? And, as indicated by kiwi’s climacteric status, it worked. Sort of. I have to say that the indoor-ripened fruits just weren’t as tasty. They’d be okay for jam, though, so perhaps next year that’s what I’ll do.

So what does this have to do with the tomatoes in the title? Continue reading

Q&A: When is it too late to transplant perennials?

Rudbeckia hirtaQ: When is it too late to transplant my flowering perennials? How late into the fall can I divide and move my plants?

A: It’s not too late! You can transplant perennials anytime until the ground freezes in the fall, or wait to transplant them in the spring. Fall is an excellent time to transplant herbaceous perennials because your plants will then have three seasons to establish a good root system before hot summer weather sets in next year. Herbaceous perennials are non-woody plants whose tops die down in the winter. They come back each year from the root system.

Continue reading