Veggie Garden 101: Inoculating Beans and Peas

Inoculating green bean (aka snap bean) seed. Photo: Liz Bosak.

Peas, green beans, dry beans, and soybeans all belong to the legume (Fabaceae) family. Legume plants can form an association with soil bacteria. A particular group of bacterial species will infect the roots and create nodules. Within these nodules, the bacteria will fix nitrogen. Nitrogen is one of the most critical plant nutrients along with phosphorus and potassium. If you have ever bought fertilizer, it will be labeled with three numbers, e.g. 15-30-15. The first number is nitrogen, second is phosphorus, and the third is potassium. The numbers mean that in 100 lbs of fertilizer there is 15 pounds of nitrogen, 30 lbs of phosphorus, and 15 pounds of potassium in 15-20-15.
If you are planting beans and peas into a new garden, it is a good idea to use an inoculant. This was a difficult product for gardeners to source at one time but it is now sold in small quantities by most seed retailers. It is important to pay attention to the description for which legumes the bacterial formulation will be effective on.
For inoculation, I drop about a half teaspoon of inoculant in a plastic container and then add a small amount of water to create a slurry. Drop a handful of seeds into the container and swirl the seed to coat. The other method is to sprinkle the inoculant in the seed furrow before covering the seeds with soil.

Add a small amount, about a half teaspoon of inoculant into a plastic container.  Photo: Liz Bosak.

Add a small amount of water.  Photo: Liz Bosak.

Drop seeds into the inoculant and swirl to coat the seeds. Photo: Liz Bosak.

Veggie Garden 101: How to Transplant Vegetable Seedlings

Cabbage transplant planted into straw and paper mulch on April 25, 2020.
Photo: Liz Bosak.

It's difficult to remember when I did not know how to transplant. The key to success is to avoid planting too deep or too shallow. The hole should be wider than the transplant's root ball. The surface of the soil near the stem should be even with the soil surface when transplanting. The exception to this rule would be leeks and tomatoes.

Healthy cabbage transplant straight from the plant tray.  Photo: Liz Bosak.

The roots of seedlings grown in plastic containers tend to circle around each other. For vegetable transplants, just loosen the roots slightly to break this pattern before putting into the soil. This is critical for root bound plants where all you can see are white roots and little to no potting soil.

Roots were lightly loosened at the base of the root ball. Photo: Liz Bosak.

After loosening the root ball, I dug a hole about twice as wide and the same depth as the root ball.

Hole in the soil through a layer of straw and paper mulch for transplanting. Photo: Liz Bosak.

Place the transplant in the hole, holding it level with the soil surface, and push the soil around to fill the hole. Be sure to firm the top of the soil to make sure the roots are in contact with the soil. The final step, do not skip this step, is to water in the seedlings. Rain will not take the place of this step unless the forecast is for more than 1 inch of rain.

Veggie Garden 101: Last Spring Frost Date and When to Plant

Cabbage transplant in April.  Photo: Liz Bosak.

One of the first obstacles for new gardeners is determining when your frost dates are for the spring and fall. They are the boundaries to a typical growing season without using any season extension techniques like row cover, unheated low tunnels, and high tunnels. Pennsylvania has a wide range of USDA hardiness zones ranging from zone 5a to zone 7b. USDA has a website with a plant hardiness by zip code tool, available here. The hardiness zones are based on the extreme minimum temperature recorded each year between 1976 and 2005.
The last spring frost and first fall frost dates are a moving target. Many people have a relative or friend that use either phenology (when certain plants bloom in the spring) or a holiday to guide when they plant certain vegetables. My Grandfather was fond of saying tomatoes were safe to plant by Mother's Day. Seed packets have a variety of instructions on when to direct seed or transplant.
Seed catalogs and packet backs are a good guide for determining when to direct seed or transplant but these usually depend on knowing when your last spring frost date is. There is general confusion about when this is because different plants can tolerate different minimum temperatures. For a comprehensive collection of first frost dates and other important weather information, visit the Pennsylvania State Climatologist's Agricultural Interests page. For central and southern Dauphin county, the average departure in spring from 36 degrees Fahrenheit is 119 to 129 Julian days, putting a conservative last frost date between April 28 and May 8. For the average departure in spring from 32 degrees, the last frost date would be between April 13 and April 22. Confusing? I like to think it is nuanced.
Gardening is both an art and a science. As soon as March hits, I start to closely track the day and night time temperatures. Every season is different. In 2020, the months flip flopped and we saw warmer weather in March than April. For cold hardy crops the instruction "as soon as the ground can be worked" applies and direct seeding and transplanting can occur before the last spring frost date. It is important to remember that seed germination and early plant growth is dependent upon the soil and air temperature. Tomatoes prefer night-time temperatures around 50 degrees Fahrenheit, too much below 50 F and the plants will suffer. A low tunnel with a layer of Agribon 19 row cover and greenhouse plastic provides about 9 degrees of warming and row cover alone about 2 degrees. For tomato transplants into a low tunnel with row cover and plastic, I typically wait until the night time temperatures are at 40 degrees or more.
Any questions? Just type them in the comments section.

Veggie Garden 101: Trellising Peas

Trellis installed for snow and snap peas on April 25, 2020.
Photo: Liz Bosak.

Early spring is the best time to grow snap, shell, and snow peas. Today, I installed a trellis for the snow pea and snap pea seedlings in the garden. Typically, in south central Pennsylvania, peas are sown in mid to late March. Once the peas reach about 4 inches in height, it is time to install a trellis. I have made the mistake in other years of waiting or forgetting to trellis the peas until they are 8 to 12 inches in height.
Metal fence posts installed with a fence pounder or sledge hammer are my favorite way to create trellises. They are an absolute necessity for tomatoes. For peas this year, I decided to use wooden stakes. I prefer to use sisal twine because it can be cut down and tossed in the compost bin. There are commercially available nylon or plastic trellises such as Hortnova. I have not explored using these because I have heard that they are very difficult to re-use.

Pea tendrils within reach of sisal twine trellis.  Photo: Liz Bosak.

Unlike morning glories or pole beans, peas are relatively indifferent climbers. The trellis needs to be within reach of the pea tendrils. These tendrils are used to clasp onto the twine and hold the pea plant upright. Without the trellis, the pea plants will cling to each other and eventually flop over onto the ground. This makes harvest difficult and likely reduces yield. The spacing for this trellis is to have two lines close to the seedling within about three inches and then the next two lines are about 6 inches from the bottom two.

First course of twine before returning with twine on other side
to complete a full course.  Photo: Liz Bosak.

In past years, I have painstakingly woven a trellis with six inch squares but I do not think the effort is worth the result. This year, I decided to use this trellis method based on what a local vegetable grower posted on their farm's facebook page. This took much less time and I think it will work at least as well as my previous method if not far better than before. After setting all the courses/runs/loops of trellis twine, I decided to make sure that each pea plant fell in between the first set of twine. I do not mind this extra effort because I have relatively few row feet. In a commercial setting, I would have run the first course and made sure the pea plants were contained at the same time to avoid going back a second time.

Wrapping around the final stake to return and complete the
course.  Photo: Liz Bosak.

If you are using metal fence posts, then you do not have to worry about pulling too tight. However, with wooden stakes, if you pull too hard, then the wooden stakes are forced to bend and other parts of your trellis will start to sag. I still had some sagging in the trellis but I do not think it will make a huge difference. This would not be the case for tomatoes. I use a similar system but I always use metal fence posts to hold the weight of the tomato plants and I pull the twine as tight as possible.
In thirty days, I will post some more pictures of the trellised peas.

Veggie Garden 101: Starting a Garden Without a Rototiller

The toughest part of gardening is starting a new vegetable garden. I have started and left many gardens over the years. In my twenties, I would use a digging fork and a shovel but it takes a lot of time, blisters, and some sore muscles. Renting a rototiller is an option if you have the money and a vehicle to transport it. A few years ago, I decided to purchase an electric, plug-in rototiller which has plenty of power for a small, less than 1500 square feet, garden.

However, if you have patience, an opaque, heavy tarp can be used to smother any grass. You will want to weight it down with something you already have- clods of sod, bricks, gallon jugs of water. Depending upon the temperature, it can take a week to kill the sod but then you are half way there.

Once the sod is dead, take a digging fork to loosen and turn the soil. A garden rake can be used to break of the clods and even out the surface.

What to watch out for:

Avoid turning the soil after rainfall. The soil will be too wet and form huge clods. Then, when they finally dry out, it will be a chore to break them apart.

Veggie Garden 101: Containers for Limited Space Gardening

Even though I have space for a large garden now, it was not always so. Community garden plots saved my gardening life for a number of years and some seasons I was limited to a container garden. However, just because it may be small doesn't mean it isn't a fabulous and creative way to garden. The container options have exploded over the last decade, everything from self-watering planters to raised container beds.

Vegetables pose an unique challenge because they tend to need lots of soil space meaning large, heavy, and expensive containers capable of holding between three and ten gallons. Luckily, felt or fabric planters are readily available through online retailers. Some of the planters are engineered to biodegrade after months or years. The main advantages to the fabric planters are low cost, lightweight - no one wants to carry an 18 inch diameter terra cotta pot with potting soil, and allow roots to breathe.

Aside from the container, the next most important factor is the potting mix/growing media. Do not purchase garden soil. It is cheap but has little to no drainage and your plants will suffer. I like to use about 80% peat-based potting mix and 20% high quality compost. If you don't have access to compost, just go with the potting soil but plan on adding a slow-release fertilizer, e.g. osmocote, to the planters.

The last critical step for growing vegetables in containers is variety selection. Plant breeders have been working over the past few decades to develop "patio" vegetable varieties. The most challenging vegetable to grow in containers, in my opinion, is the tomato plant. "Patio" tomato varieties are usually determinant plants. This means that the plant sets all of its flowers at one time so you get a narrow harvest window versus an indeterminant variety that continues to set flowers and fruit over a long season. However, indeterminant tomatoes tend to be large, generally over six feet in height, and difficult if not impossible to grow in a container.

Veggie Garden 101: Frost Protection

Low tunnel with Tufflite plastic and Agribon-19 row cover.
Photo: Liz Bosak.

When nighttime temperatures dip towards 32 degrees Fahrenheit, many vegetable plants benefit from some frost protection. Commercial row cover fabrics, such as Agribon 19, provide about 2-3 degrees of frost protection. Heavier weight row cover can provide closer to 5 degrees Fahrenheit. In general, the heavier the fabric means less light penetration. Adding a layer of greenhouse plastic adds at least 9 degrees. If you don't have a commercial row cover fabric, you can use a old sheet for the night and remove in the morning.

Low tunnel with Agribon -19 row cover. Photo: Liz Bosak.

The trickiest part of effectively covering plant rows is supporting the cover above the plants if possible and securing the cover. Sandbags filled with sand, gravel, or soil work well. The row cover pegs only work well in loose, deeply tilled soil or in sandy soil. Shovel fulls of soil placed on the edge of the row cover takes time but it's free.
What to watch out for: 1. if the daytime temperatures go above 60 degrees, it is best to remove the row cover fabric.2. if using row cover + plastic, remove both layers during the day if temperature exceeds 60 F. These recommendations are for cool weather loving crops such as spinach, lettuce, broccoli, kale, mustard greens, arugula, and peas.
Supporting the row cover with wire, galvanized steel, or pvc/plastic hoops prevents the frost from significantly damaging the plants where the leaves touch the frosty row cover at night.