Tag Archives: soil building

6 Ways to Improve Soil Fertility

As grocery, fertilizer, and other prices continue to rise, many backyard gardeners are digging deep to grow their own food. Whether you’ve been gardening for 20 years or planted your first plot this spring, maintaining or building healthy, fertile soil is probably a top concern. If you’re on a budget, purchasing fertilizer or other organic garden amendments can be a strain or even out of reach entirely. Thankfully, there are a few affordable or even free ways to improve soil fertility. 

Start composting. 

In a previous post, I referred to compost as black gold, and I wholeheartedly believe that good finished compost is one of the best garden amendments you can have. It adds fertility, improves soil structure, encourages beneficial fungi and bacteria, and more. Composting also helps keep unnecessary items out of landfills. 

Here are a few of the items you can compost and keep out of a landfill:

  • Vegetable Scraps
  • Stale or Moldy Bread, Crackers, Chips, etc.
  • Egg Shells
  • Grass Clippings
  • Coffee Grounds
  • Tea and Tea Bags
  • Leaves

If you want to learn more about composting from what bin or system to use, maintaining your compost, and what to put in it, visit our post, Black Gold: Making Compost.

Water with compost, comfrey, grass-clipping, or manure tea.

If your plants need a fast-acting boost, watering with a bit of one of these DIY liquid fertilizers may do the trick. It may sound a little gross and can be a bit smelly, but it’s easy to do and worth it!

All you need is compost, comfrey leaves, grass clippings, or manure, a five-gallon bucket or another similar container, water, and some material for filtering like an old pillowcase or cheesecloth. 

Get the details from our post, DIY Compost Tea.

Bag and use your grass clippings.

While I’m all for going no-mow whenever you can and using alternatives like wildflower plantings in place of lawns, I do understand that mowing some areas is nice or even necessary. Whether you’re mowing around your garden to keep the grass from creeping in, a play area for your kids, or just around your home, you can put those grass clippings to good use!

A mower with a bagger will allow you to collect and use grass clipping as mulch or ingredients in compost or liquid fertilizer. However, you may not want to bag your clippings all the time. Just like grass clipping add fertility to your garden, they help keep your yard fertile and grass looking nice as well.Cover Crops to Improve Soil Fertility

Grow cover crops. 

Cover crops aren’t a quick fix, nor are they free, but I think their benefits still outweigh their negatives. Cover crops add fertility and organic matter to the soil, help keep down weeds, provide habitat for pollinators and other beneficial insects, and prevent erosion. They’re also more affordable than buying fertilizer over the long term. 

Different cover crop species come with different benefits, and you may want to do a bit of research before selecting one. 

Some cover crops like buckwheat are “winter-kill,” meaning they die back with frost. Some no-till gardeners use these as mulch for the following spring. Just rake the dead plant material back to seed or transplant your crops.

Clover and other cover crops in the legume family are nitrogen-fixers meaning that they take nitrogen from the air and add it to the soil as they grow. You can read more about how nitrogen fixation works in our post, What’s a Nitrogen Fixer?

If you have a hardpan or compacted soil, you may want to look into cover crops like Deep-Till radishes. These and other large rooted, tough cover crops will help break up compacted soil and hardpan, aerate the soil, add organic matter and allow water to soak in faster.

Here are a few great cover crop options:

While many cover crops are planted in a rotation, leaving beds free of crops for a year or in seasons when beds are not in use, there is another great option, especially for no-till gardeners. You can grow a crop like white clover in the paths between permanent beds. White clover will tolerate being walked on and mowed, providing a great path and source of mulch.

Look for people getting rid of “mulch hay” or straw.

Sometimes, you can find old or “mulch” hay or straw listed for cheap or free on sites like Facebook Marketplace. Often, these are bails that have gotten wet, moldy, or are just no longer fit for animal feed or bedding, but they’re perfect for the garden! 

Use old hay or straw to create lasagna gardens, mulch around plants, add to your compost, or create hugelkultur mounds.

Talk to the farmer you’re purchasing or getting the hay from and make sure it’s not from a field that has been treated with herbicides. Some folks also don’t like using hay because it contains weed seeds. Straw is the stalks from a wheat harvest and is generally free of seeds.Woodchips for Soil Fertility

Search for free wood chips.

Wood chips are another great source of organic matter and work well as a mulch, helping keep the soil cool and moist and blocking weeds. They’re slower to break down than other mulches like grass clippings, hay, or straw but will eventually turn into good quality soil. They’re also an excellent habitat for beneficial insects.

It’s often easy to find free wood chips in the summer when power companies are cutting trees and limbs away from power lines. Contact your local company or stop and ask workers you see. Sometimes, they may even be willing to dump a whole truckload at your home for free if they’re working nearby. Occasionally, local garden or hardware stores will source wood chips from electric companies, and you can go and fill coats or a truck for cheap or free. 

Avoid using the dyed black or red wood chips that come in bags from hardware or big box stores. These aren’t organic and are generally much more expensive.

Improving your garden starts with the soil. Using these methods and amendments, you can add fertility to your soil on any budget. They’re great for your garden, good for the environment, and generally pretty simple. How do you add fertility to your organic garden?

Improving Heavy Clay Soils

Gardeners rarely begin their journey with a plot of perfect soil, but it’s something we all dream about. In the Southeast, many gardeners have to work with heavy clay soils. While clay soil is rich in minerals and many nutrients, it’s prone to compaction, doesn’t drain well in wet weather, and doesn’t hold water well during droughts. Growing certain root crops like large carrot varieties can be especially tough.

Clay soils are a great foundation to improve on. Here are a few organic methods to improve your heavy clay soil. 

Practice No-Till (or minimal-till) Agriculture

It may sound counterintuitive, but tilling can make clay soils worse. Tilling increases soil compaction and kills beneficial fungi and micro-organisms. 

Cover Crops

Cover crops add nutrients and organic matter to the soil. Great choices for improving clay soils include buckwheat, clover, and wheat. Clover has the benefit of being a nitrogen-fixing legume, meaning that through a symbiotic relationship with bacteria, it captures nitrogen from the air and adds it to the soil.

You may also want to mix in large or deep-rooted cover crops like daikon radishes, lava beans, and alfalfa. These crops help break up compacted soil and create channels for air and water as their roots decompose.

Chop & Drop

You can also use a method commonly used by permaculturalists called “chop and drop.” This method involves growing crops like comfrey, pigeon peas, moringa, sun hemp, and sorghum. These crops are chopped and dropped on the soil to decompose. Comfrey is a popular choice for this in perennial gardens and fruit tree guilds.

Broadfork

Broadforking your soil is a great way to loosen soil without disturbing the layers or structure. It helps mitigate compaction and preserve beneficial organisms and fungi in the soil. 

Create Permanent Beds

Even just walking on your garden soil can cause severe compaction. Creating permanent beds that you don’t till, step on, or use machinery will help make light, fluffy soil. 

Use Terraces or Swales

If your property has heavy clay soil and a slope, you’ll probably deal with water issues. Planting in rows or terraces that are perpendicular to the slope of the land will help slow down the water in your garden and reduce erosion issues. Swales built on contours take this further and are a great way to catch large amounts of rainwater, allowing your plants to access it slowly, even on significant slopes. 

Spread Compost

Finished compost is the quickest way to beef up the organic matter in your soil. Adding a couple of inches of compost to each bed adds nutrients, improves water retention and drainage, and lightens the soil.

Use Mulch

Mulch helps block weeds, hold moisture, and keep soil temperatures cool. It also adds a lot of organic matter to your soil as it decomposes. Any organic mulch can help improve your clay soils, including straw, leaves, grass clippings, woodchips, and hay. Keep in mind that hay tends to have a lot of weed seeds.

Grow Varieties Adapted to Heavy Clay Soils

Improving clay soils isn’t something that happens overnight, especially in large gardens. If you’re planting in a garden with heavy clay soils this year, try some varieties that are adapted to these conditions.

  • Chantey Red Core Carrots
    This blocky, broad-shouldered variety with a blunt tip is well-suited to growing in clay. It was introduced from France in the 1800s.
  • Danvers 126 Carrots
    These carrots taper to a blunt point and are especially suited to growing in clay soil. The strong tops aid harvesting.
  • Everona Large Green Tomatillo
    These plants produce large, tasty tomatillos and thrive even in heavy clay soil and drought.  Seed collected by Barbara Rosholdt from tomatillos planted by Mexican workers at the Everona sheep dairy near Unionville, VA. Introduced in 2008 by SESE.
  • McCormack’s Blue Dent
    This beautiful dent corn makes delicious light blue flour and is especially suited to the eastern U.S., clay soils, and drought-prone areas. Introduced in 1994 by SESE. Bred by Dr. Jeff McCormack from a cross between Hickory King and an unnamed heirloom blue dent.
  • Oxheart Carrots
    A good carrot choice for shallow or heavy clay soils that most carrots don’t like. Dating to 1884, this variety produces thick, sweet “oxheart”-shaped carrots, 5-6 in. long and 3-4 in. wide, weighing up to a pound!
  • Pike Muskmelon
    Bred specially for growing in unirrigated clay soil, this vigorous melon has outstanding flavor and good disease-resistant. Introduced in 1935, Aaron Pike of Pike & Young Seeds; seedstock supplied to SESE by Aaron Pike’s niece.
  • Tennessee Red Valencia Peanuts
    This pre-1930 produces rich, sweet peanuts with red skins. It’s easy to grow without hilling, even in clay soils.
  • Texas Gourdseed Corn
    Originally brought to south Texas by German farmers who migrated from Appalachia during the late 19th century, this variety withstands drought and does well in clay soil. In south Texas, this is considered to be the best choice for tortilla flour.
  • Turga Parsnip
    This Hungarian heirloom produces short, stout roots that are good for heavy clay soils.
  • Southern Peas (Cowpeas)
    These productive peas are well-adapted to poor soils and drought. We carry 16 varieties at SESE.

Using Manure in the Garden

It’s now believed that farmers have been using manure to fertilize their crops for at least 8000 years! Spreading manure on fields and gardens to increase soil fertility has long been common, especially when most folks were keeping livestock. Today, it can be more tricky. So whether you’ve got your own backyard farm or not, here are a few things you should know about using manure in the garden. 

Pros

  • It’s full of nutrients! Manure is an excellent source of primary plant nutrients nitrogen, potassium, and phosphorus. It also includes secondary nutrients; calcium, magnesium, and sulfur that may not be found in commercial garden fertilizers.
  • Manure adds organic matter and improves soil structure. This allows optimum root growth and increases the soil’s ability to hold moisture.
  • You can often find manure for free or use your own from your own livestock.

Cons

  • Fresh manure can contain bacteria that can contaminate crops and make you sick.
  • It often contains weed seeds.
  • It may contain pesticides, herbicides, or other chemicals.
  • Fresh manure contains high levels of nitrogen, ammonia, and salts which can burn crops. 

Sourcing Good Manure

If you own livestock, using their manure is the best choice. To fertilize your garden, you can use chicken, goat, cow, horse, rabbit, and other livestock manure. Avoid cat and dog waste as their feces can contain toxins and heavy metals that will remain in your garden. 

If you don’t own animals, it may be possible to source manure from a local farm. However, you may want to ask some questions. Herbicides can stay in manure and ruin your garden, so it’s essential to ask if the animals were allowed to graze where an herbicide was sprayed. 

It’s also worth noting that not all animal manures are the same. Manure from herbivores like horses and cows has a lower nitrogen to carbon ratio than omnivore manure like that from pigs and chickens. Therefore herbivore manure won’t burn your crops even if it’s fresh. You should also note that horses don’t digest seeds, so horse manure will have more weed seeds in it. 

Composting Manure

Some of the “cons” of manure are easily taken care of by composting it. Composting your manure will kill any bacteria and allow it to mellow, so it’s not high in nitrogen, ammonia, or salts and won’t burn your crops. A good, hot compost pile can also render weed seed inviable. 

To compost manure, you’ll want to follow the same techniques we discussed in Black Gold: Making Compost. Mix your nitrogen-rich manure with good sources of carbon such as old leaves, straw, or shredded paper; alternate layers as you build your pile. Keep the pile moist and turn it over every few weeks to encourage aerobic decomposition. It’s ready when it looks like black, crumbly soil and is no longer hot or smelly. 

You can apply composted manure to the garden the same way you use your regular compost. Spread a few inches on a bed before planting, add it to homemade potting mixes, or side-dress crops. 

Aging Manure

Your other option is to age manure rather than compost it. It’s exactly like what it sounds. You pile it and leave it. This process can take longer than composting, particularly if you’re starting with manure that’s high in nitrogen, like pig manure. 

Applying Fresh Manure

If you want to apply fresh manure, you need to select “cool” manure like horse, cow, or rabbit manure. Other manures, including goat, poultry, and pig, may burn your crops. Goat and sheep manure may be okay if it’s mixed in with carbon-rich bedding like straw or hay.

One of the safest ways to use fresh manure is to follow the USDA National Organic Program Guidelines. They state that if the crop may come into contact with the soil, whether it’s touching them directly like with beets or splashing on them like with Swiss chard or cucumbers, it must be applied 120 prior to harvest. If the crop won’t be in contact with the soil like corn or dry beans, the manure must be applied 90 days prior to harvest. 

It’s a long time! This timeframe keeps crops safe from bacterial contamination such as E. coli and Salmonella. However, many home gardens don’t feel the need to follow such stringent guidelines. Just make sure you wash your veggies well if there’s a chance they’ve come into contact with the manure, especially if you don’t know where the manure came from.

Can You Use “Humanure?”

Using composted human waste to fertilize crops used to be common throughout much of the world. Composting human waste can reduce pollution and water consumption. Setting up a composting toilet is also much easier and cost-effective than installing a septic system and is a popular choice for off-grid and tiny homes. 

So is it safe? Yes, when done correctly. There are a number of fairly basic considerations to composting human waste. For example, you want to ensure your compost bins aren’t on wet ground or somewhere they could contaminate ground or surface water. You should also compost your waste for a year before use, and you should use it around fruit trees, berry bushes, and ornamental plants where it won’t get on food crops. Modern Farmer has a more detailed piece on humanure you can find here.