Sweet potatoes are ideal for filling the gap between summer and fall crops as they have a long growing season. Photo by Janis Piotrowski.
Take the Summer Off, Grow a Cover Crop
As gardeners in the northern states plant and harvest crops until fall, those in the south know that summers can be brutal. In Florida and other areas in the deep south, temperatures can reach triple digits by the summer solstice, and humidity can make it feel like you’re swimming through the air. Pests, from mosquitos to stink bugs, descend quickly, making it no fun to spend hours weeding and watering in the sweltering heat, only to watch your plants struggle to survive. This is why we take advantage of the summer swelter by relaxing with some ice-cold lemonade and enjoying a well-deserved break.
However, while we take a summer gardening hiatus, it’s essential not to leave our soil bare. Fallow soil can become compacted and lose its structure, as there are no roots to create air channels that allow water from frequent summer storms to penetrate the soil. This makes it more challenging for plants to grow in upcoming seasons and can lead to erosion, nutrient depletion, and weed growth. By planting cover crops during the off-season, gardeners can prevent these issues and improve the health of their soil for fall planting. Cover crops offer a multitude of benefits, such as adding nitrogen to the soil, increasing organic matter content, suppressing weeds, breaking pest and disease cycles, and even providing a crop to harvest in the fall.
Fix Nitrogen with Legumes
Cowpea is a summer annual legume that can fix nitrogen, improving soil fertility for fall crops. Photo by Michasia Dowdy, University of Georgia, Bugwood.org.
Summer cover crops are a great way to keep your garden healthy and productive during the off-season, and leguminous crops like cowpeas, soybeans, and sunn hemp can add an extra boost to your soil’s fertility. These legumes have a unique ability to form a symbiotic relationship with nitrogen-fixing bacteria in the soil, allowing them to convert atmospheric nitrogen into a form that plants can use for growth.
Apart from their nitrogen-fixing properties, leguminous cover crops also have deep taproots that can help to break up compacted soil, improve water infiltration, and reduce soil erosion. When planted in dense stands, they can even suppress weed growth, making it easier to maintain your garden’s health.
It’s important to remember to terminate your leguminous cover crops at the bloom stage, as this is when the nitrogen-fixing nodules on the roots are at their peak. By cutting them down at this point, you can help to release the fixed nitrogen back into the soil, where it will be available for future crop use.
Increase Organic Matter with Buckwheat
Buckwheat not only builds organic matter in soil but it also attracts pollinators. Photo by Russ Ottens, University of Georgia, Bugwood.org.
Buckwheat is an ideal summer cover crop for gardens with poor, sandy soil. It is a rapid grower and can produce a large amount of biomass in a short period of time, which can be used to increase soil organic matter content, improving soil structure. The cover crop’s dense, fibrous root system provides ample surface area for nutrient uptake and helps prevents erosion.
Another major benefit of planting buckwheat is its ability to attract beneficial insects, particularly pollinators like bees and butterflies, which can help increase the yield of crops that rely on pollination for fruit set. Additionally, buckwheat is known for attracting predatory wasps, which can help control insect pests. Buckwheat also has the ability to scavenge phosphorus from the soil, making it available for other crops.
To prevent buckwheat from becoming weedy, it is important to terminate it before it goes to seed. This can be achieved by chopping it down when it starts to flower and leaving it to decompose in place.
Suppress Nematodes with Marigolds
French marigolds can help suppress root-knot nematodes. Photo by North Carolina, USDA APHIS PPQ, Bugwood.org.
Nematodes are microscopic, unsegmented roundworms that can be either be free-living or plant parasites. Among them, the plant-parasitic species, such as the root-knot nematodes, can cause severe damage to crops and even lead to their demise. They are difficult to control as they reside underground or inside plants, and nematicides are not easily available to home gardeners.
However, planting cover crops like African or French marigolds before the main crop can significantly reduce nematode populations. These marigolds release alpha-terthienyl, which suppresses not only root-knot nematodes but also other disease-causing organisms.
Apart from marigolds, several other summer cover crops like sunn hemp and velvetbean can also suppress nematodes, especially for root-knot and sting nematode control.
Cover Crops for the Dinner Table
Growing cover crops that serve a dual purpose of providing ground cover during the hottest months and yielding edible produce in the fall is an excellent way to make the most of garden space. Some examples of such crops are sweet potatoes, field peas, and daikon radishes.
Sweet potatoes are ideal for filling the gap between summer and fall crops as they have a long growing season. They have a deep root system that helps break up compacted soil, and their vines provide ground cover, reducing soil erosion. In the fall, their tubers can be harvested after the leaves have died back to make a nutritious and delicious addition to any meal.
Field peas are a versatile crop that not only provide benefits to the soil as nitrogen fixers and ground covers but also offer delicious edible pods if allowed to develop. There are many types of field peas for which to choose, including black-eyed peas, crowder peas, and cream peas. Pods can be harvested in the fall and used to enhance the flavor of stews, salads, and soups.
Daikon radishes are an excellent cover crop that grow deep to break up soil and they have plenty of flavor for the dinner table. Photo by Guodong Liu, UF/IFAS.
Daikon radishes have a deep taproot that can help break up compacted soil, and their foliage can help suppress weed growth. In addition, daikon radishes can be harvested in the fall and can be used in a variety of dishes such as soups, salads, and stir-fries.
Timing is Everything
To make the most of your summer gardening break, plant cover crops as soon as you conclude your spring harvest, typically from late May through early July. Scatter the seeds evenly over the bed and lightly rake them into the soil. It is important to keep the soil moist during the germination period, which typically lasts four to 10 days depending on the crop.
Regular monitoring of your cover crops as they grow is essential to ensure they are terminated at the appropriate time, preventing them from becoming weeds and competing with other crops. Once terminated, you can leave the cover crop residue on the soil surface as a mulch or incorporate it into the soil.
So, this summer, stay cool and let your cover crops take the heat as they improve soil fertility, increase organic matter, prevent erosion, suppress nematodes, reduce weeds, and even provide food for a fall harvest.
Would you like to make money off your land? Are you looking to diversify your current plans on your property? Jackson County is hosting a fruit and vegetable meeting on January 26, 2023, and this just may be the perfect way to start off your new year!
Photo by Molly Jameson.
When thinking about what it means to be successful in planting your garden or having fruit trees, often the first thing that comes to mind is a healthy quality crop. This starts with the health of your soil. We will have two specialists that cover soil health and the benefit of adding cover crops to your rotation during the off season. The second thing that might come to mind when wanting to be successful is how to start? how much time do I have to devote to gardening? and how much do I want to do? This meeting will also have a specialist coming to Marianna to cover how to get started on a property with a specialty crop. Even though this information may be geared towards new farmers, it could also be very useful to new land owners and community residents just wanting to do more on their property. You may find that you have so much extra produce that you want to have a little fruit stand!
There will also be a session on the importance of drip irrigation, fertigation and how to implement these practices. Drip irrigation will not only save you money in the long run with the use of less water, but it is also much better for overall plant health by reducing pest and disease problems. Fertigation is the process of adding soil amendments, water amendments and other water-soluble products into an irrigation system. This process can be both beneficial to the plants and cut back on the time it would take to fertilize by hand.
The next session on specialty vegetable and fruit crops will teach about the various exciting specialty crop opportunities in the Tri-State area such as artichokes, blackberries, Seminole pumpkins, and more. Finally, the meeting will also cover cucurbit disease updates and will be extremely useful if you already have a field or garden of watermelons, cucumbers, or squash! Come with questions! CEUs will be offered as well if you are a homeowner that holds a pesticide license.
Organic matter is the “glue” that will hold your soil together. Photo by John Edwards.
While, the audience for this conference is primarily small to medium sized, diversified cucurbit and vegetable producers in the tri-state region including the counties in the Panhandle, Alabama, and Georgia, the residential community is welcome to attend and will truly benefit with learning about soil health, cover crops, fertigation, drip irrigation, and specialty crops. The conference will be held at the Jackson County Extension Office in the Peanut Hall. We are planning a full morning with educational sessions and lunch to follow.
This meeting will be $5 at the door and pre-registration is highly encouraged. Please call our office at 850-482-9620 to reserve your seat and if you have any questions.
Tri-State Fruit and Vegetable Meeting
Thursday, January 26, 2023, 8:00 am- 1:00 pm at the Jackson County Agriculture Offices Auditorium, 2741 Penn Ave., Marianna.
Yay, we are halfway through with August and our summer is winding down! This is the perfect time to start prepping for that fall garden. Growing a productive fall vegetable garden requires thoughtful planning and good cultural practices. This process consists of selecting a site, planning the garden, preparing the soil, choosing the seeds and plants, planting a crop, and nurturing the plants until harvest time. In the Florida Panhandle it can be a challenge to get cool season crops started; there is a balance in starting them early enough to allow them to mature (50-60 days) before a hard frost and getting them through the end of a hot summer.
August and September are the main planting times for a fall garden. There are several cool-season crops and a final crop of warm-season vegetables that can be planted. Some good warm season crops are lima beans, cucumbers, eggplant, peppers, and tomatoes. Going into September it will be a good time to establish strawberry plants. Some good vegetables to start growing just around the corner are broccoli, carrots, cabbage, collards, mustard, and Swiss chard. https://edis.ifas.ufl.edu/NorthFloridaGardeningCalendar Herbs that do well are cilantro, parsley, and lemongrass. Mint, oregano, and thyme should be planted in containers as they tend to spread. Mexican tarragon, mint, rosemary, and basil will also do well in September. See Herbs: http://edis.ifas.ufl.edu/topic_herbs
Transplants from the local garden center will get the garden off to a fast start while seeds will offer more varieties to choose from. It is also important to think about your location. A vegetable garden can be in the ground, a raised bed, or even grown in containers. Your plants will need more than just a place to grow. They will also need sunlight, water, air, soil, fertilizer, and care. Most vegetables require at least 8 hours of sunlight. Keep an eye out for pest problems such as insects, diseases and weeds because they will continue to flourish in warm temperatures and high humidity. To help conserve soil moisture a layer of newspaper and mulch can be placed between the rows. Mulch also aids in weed control.
Raised beds are an excellent way to get started with gardening. Photo by Molly Jameson.
The result of a beautiful, successful vegetable garden is fresh produce to eat, share with neighbors, family, and friends and even the possibility to sell your harvest. With patience and practice your gardening skills will improve every year! Follow the above few tips and you will be well on your way to a great harvest! For more information about starting a fall garden or any other horticultural or agricultural topic, contact your local UF/IFAS County Extension Office. Happy Gardening
One of the major recent movements in production agriculture has been the widespread adoption of cover crops. This practice gives farmers a host of benefits, from erosion prevention to nutrient retention and recycling. However, using cover crops isn’t just for large scale farming operations. Hobby vegetable gardeners can absolutely employ similar systems on a smaller scale to reap the same benefits. For the past two years, I’ve used Buckwheat to provide a soil building cover during the heat of summer between spring and fall gardens. This winter, after my fall greens garden succumbed to frost, I decided to employ the same tactic with a mix of Red Clover (Trifolium pratense), White Clover (Trifolium Repens), and Crimson Clover (Trifolium incarnatum) to enhance my soil during the coldest months until spring tomato planting arrives!
Clover mix used as a cool season cover crop in raised beds. Photo courtesy Daniel Leonard.
While there are many different species of plants (rye, oats, wheat, various brassicas, etc.) that can be planted in November or December as cool season covers to deliver benefits like winter weed suppression, enhance soil organic matter, retain and harvest leftover nutrients, and provide habitat for beneficial insects, I chose Clover for an additional reason. In addition to the above benefits, Clover is a legume and also fixes atmospheric nitrogen, making it available for subsequent plantings! Not only is Clover an excellent soil cover, but it also provides some nitrogen fertilizer to the following vegetable garden!
Growing Clover, while not quite as simple as Buckwheat or small grain covers like oats and rye, is relatively easy for most gardeners. The first step is selecting which clover species and/or variety to grow. I chose a mix of Crimson, White, and Red Clover simply because I had several pounds of each left over from a previous field planting. However, any one of the three may be used by themselves or in various combinations. All are excellent choices for garden cover crops and have similar growing requirements. Crimson Clover is the most readily available, but all three species can be found at most farm and garden supply stores.
The next step is to prep your garden beds for clover seeding. I thoroughly remove weeds from my raised beds, lightly till the top couple of inches of soil, and rake to provide a level surface. Since clover seed is tiny, a smooth, clean seedbed is a must for excellent germination. Once this is done, your next should determine how much seed to plant. Recommended clover seeding rates are usually given on a per acre basis and range from 3-4 lbs/acre (White Clover) to 20-25 lbs/acre (Crimson Clover). Given these seeding rates, planting in a 4’x8’ (32 ft2) raised bed is only going to require a miniscule amount of seed.
Clover mix used as a cool season cover crop in raised beds. Photo courtesy of Daniel Leonard.
To ensure a good stand while minimizing risk of overplanting, I mix equal parts clover seed and either sand, vermiculite, or other media similar in size to clover seed and hand scatter over the surface of my beds, making sure to uniformly cover the entire bed. If you think the stand is too thick, you can always hand-thin after emergence.
As a group, clovers prefer moist soil that is not allowed to dry out completely. This isn’t usually a problem given the Panhandle’s frequent rainy cold fronts in winter, but if rainfall is inconsistent, some irrigation will be required. Supplemental fertilizer isn’t normally necessary when planting a clover cover in vegetable gardens because nutrients remaining from the previous veggie crops are usually sufficient for growth and development (N especially is not needed as legumes produce their own through N fixation). 2-3 weeks before you’re ready to plant your spring veggies, chop the clover cover into the top few inches of your bed to terminate it and release its nutrients back into the garden. It’s that easy!
Planting a winter legume cover crop like clover is a great way to harness the benefits of cover crops for your spring veggies and enhance the aesthetics of your otherwise barren and drab garden beds! For more information about growing winter cover crops or any other horticultural topic, contact your local UF/IFAS County Extension office. Happy Gardening!
Daniel Leonard, Horticulture Agent at UF/IFAS Extension Calhoun County, answers commonly asked questions about raised bed gardening. In the video he discusses construction materials, the type of soil to use, fertilization, crop rotation, cover crops, and smaller container gardens.
2020 has not been the most pleasant year in many ways. However, one positive experience I’ve had in my raised bed vegetable garden has been the use of a cover crop, Buckwheat (Fagopyrum esculentum)! Use of cover crops, a catch-all term for many species of plants used to “cover” field soil during fallow periods, became popular in agriculture over the last century as a method to protect and build soil in response to the massive wind erosion and cropland degradation event of the 1930s, the Dust Bowl. While wind erosion isn’t a big issue in raised bed gardens, cover crops, like Buckwheat, offer many other services to gardeners:
Buckwheat in flower behind summer squash. Photo courtesy of Daniel Leonard.
Covers, like Buckwheat, provide valuable weed control by shading out the competition. Even after termination (the cutting down or otherwise killing of the cover crop plants and letting them decompose back into the soil as a mulch), Buckwheat continues to keep weeds away, like pinestraw in your landscape.
Cover crops also build soil. This summer, I noticed that my raised beds didn’t “sink” as much as normal. In fact, I actually gained a little nutrient-rich organic matter! By having the Buckwheat shade the soil and then compost back into it, I mostly avoided the phenomena that causes soils high in organic matter, particularly ones exposed to the sun, to disappear over time due to breakdown by microorganisms.
Many cover crops are awesome attractors of pollinators and beneficial insects. At any given time while my Buckwheat cover was flowering, I could spot several wasp species, various bees, flies, moths, true bugs, and even a butterfly or two hovering around the tiny white flowers sipping nectar.
Covers are a lot prettier than bare soil and weeds! Where I would normally just have either exposed black compost or a healthy weed population to gaze upon, Buckwheat provided a quick bright green color blast that then became covered with non-stop white flowers. I’ll take that over bare soil any day.
Buckwheat cover before termination (left) and after (right) interplanted with Eggplant. Photo courtesy Daniel Leonard, UF/IFAS Calhoun County Extension.
Now that I’ve convinced you of Buckwheat’s raised bed cover crop merits, let’s talk technical and learn how and when to grow it. Buckwheat seed is easily found and can be bought in nearly any quantity. I bought a one-pound bag online from Johnny’s Selected Seeds for my raised beds, but you can also purchase larger sizes up to 50 lb bags if you have a large area to cover. Buckwheat seed germinates quickly as soon as nights are warmer than 50 degrees F and can be cropped continuously until frost strikes in the fall. A general seeding rate of 2 or 3 lbs/1000 square feet (enough to cover about thirty 4’x8’ raised beds, it goes a long way!) will generate a thick cover. Simply extrapolate this out to 50-80 lbs/acre for larger garden sites. I scattered seeds over the top of my beds at the above rate and covered lightly with garden soil and obtained good results. Unlike other cover crops (I’m looking at you Crimson Clover) Buckwheat is very tolerant of imperfect planting depths. If you plant a little deep, it will generally still come up. A bonus, no additional fertilizer is required to grow a Buckwheat cover in the garden, the leftover nutrients from the previous vegetable crop will normally be sufficient!
Buckwheat “mulch” after termination. Photo courtesy of Daniel Leonard, UF/IFAS Calhoun County Extension.
Past the usual cover crop benefits, the thing that makes Buckwheat stand out among its peers as a garden cover is its extremely rapid growth and short life span. From seed sowing to termination, a Buckwheat cover is only in the garden for 4-8 weeks, depending on what you want to use it for. After four weeks, you’ll have a quick, thick cover and subsequent mulch once terminated. After eight weeks or so, you’ll realize the plant’s full flowering and beneficial/pollinator insect attracting potential. This lends great flexibility as to when it can be planted. Have your winter greens quit on you but you’re not quite ready to set out tomatoes? Plant a quick Buckwheat cover! Yellow squash wilting in the heat of summer but it’s not quite time yet for the fall garden? Plant a Buckwheat cover and tend it the rest of the summer! Followed spacing guidelines and only planted three Eggplant transplants in a 4’x8’ raised bed and have lots of open space for weeds to grow until the Eggplant fills in? Plant a Buckwheat cover and terminate before it begins to compete with the Eggplant!
If a soil building, weed suppressing, beneficial insect attracting, gorgeous cover crop for those fallow garden spots sounds like something you might like, plant a little Buckwheat! For more information on Buckwheat, cover crops, or any other gardening topic, contact your local UF/IFAS County Extension Office. Happy Gardening!
