Prepare Clay Soil for Spring Planting

One of the major considerations when putting in a new garden is soil texture. The mineral make up of soil is a mixture of different sized particles: sand, silt and clay. Each component plays an important role in the soil’s structure, impacting how well roots can grow and how much water and nutrients are available. The goal is to find a good balance.

Ideally your garden’s soil will contain at least 20% clay. Soil with over 35% clay is considered “clay soil.”

Clay soil hold a lot of water (up to eight times as much as sandy soil) and are slow to dry out. This is an advantage in times of drought, but in wet climates it means they get waterlogged easily. Wet clay soils tend to be cold and slow to warm up in spring. It’s no wonder that many plants don’t over-winter well in clay soils.

Additionally, most plant roots have a hard time penetrating clay soil. The pores are so small and the particles so densely packed that plants will struggle to grow and thrive.

If your garden has clay soil, don’t give up hope. Clay soils can be heavy and difficult to work with, but if you persevere they can be very fertile and productive.

Use the tips below to turn your clay soil into an environment your plants and other beneficial organisms will love.

Blue spade in garden bed. Photo source: Markus Spiske, UnsplashTiming is everything
Limit cultivation to times when soil is not too dry or wet. If you work with dry clay soil it will be so hard it is almost impossible to dig and may crack into large chunks that crumble to dust. When this dust gets wet it sets rock hard, almost like plaster. It’s usually pretty obvious when it’s too dry to work with, and you may need to add water via irrigation, or wait for a soaking rain to soften the ground.

While working with dry clay soil is difficult, cultivation of wet clay is even worse. Wet clay soil compacts very easily when you put any pressure on it, creating a sticky mass that is also hard to penetrate. One sign your soil is too wet is when you leave shiny footprints where you’ve walked because the water has been squeezed from the soil.

Amending clay soil
Add well-decomposed organic matter like compost to help particles cluster together and form larger aggregates. This will improve drainage and aeration.

You can improve clay soil’s structure by adding a mix of 80% gypsum and 20% dolomitic lime. Use an ounce of this mix per square foot of soil in spring and again in fall. This may be repeated for a second year, while also adding as much organic matter as possible.

Adding calcium may be useful to improve soil structure temporarily, until you can get sufficient organic matter and soil life into the soil. But this only works if the soil is low in calcium.

Be sure to double dig to thoroughly incorporate organic matter and calcium, as well as fertilizer and other minerals your soil may need.

Garden fork and shovel in grassLong-term solutions
Use green manures to improve structure. Growing a green manure crop will protect the soil surface as well as add organic matter when you dig it in at the end of its season.

In autumn, when it’s relatively dry, roughly dig the soil and leave it over the winter for frost to break down the large clumps.

Other suggestions for working with clay soil
Use raised beds to improve aeration and prevent future compaction. Build them high to help them drain and warm up.

Slope the site slightly so the soil can drain more quickly.

Never allow clay soil to get so dry that is cracks. These cracks increase evaporation and make the soil hard to re-wet because water simply drains away down the cracks. If it does dry out, cultivate the soil surface.

The trick to a successful first garden: start out small

You might not think so from the countless words that have been written about it, but vegetable gardening is a pretty simple process. Plants are genetically programmed to grow (even our pampered crop plants) and all you have to do is give them the right things at the right times. You take seed, put it in the soil and it grows. The basic requirements are soil, sunlight, seed, water and motivation. Continue reading “The trick to a successful first garden: start out small”

Sugar Snap Peas

Have you considered growing peas? Looking for something to feed your sweet tooth, straight from the garden? Look no further than the Sugar Snap pea. There’s a reason they’re called “garden candy.”

The Sugar Snap is actually a relative newcomer to the garden (first introduced in 1979), but it is now established as one of the great treats of spring. When my Sugar Snaps start to ripen they become the center of the garden and remain so until all the pods are gone.

The Sugar Snap differs from traditional garden peas (like Green Arrow) in that the whole pod is edible, and differs from the edible podded snow peas (like Mammoth Melting) in that the pod is fat, sweet and delicious.

As the whole pod is edible they produce a significantly bigger harvest and don’t need shelling. The original Sugar Snap variety was so successful it eventually spawned a whole range of snap peas: bush varieties, disease resistant types and some without strings. There are now even yellow, purple and pink tinted types.

The Sugar Snap was hailed as a revolutionary new kind of pea when it appeared, but it wasn’t actually as new as it seemed at the time. It turns out that the Amish have been growing snap peas for a long time and they are so similar that a casual observer probably wouldn’t be able to tell the difference.

Should I grow peas?
Peas (along with beans) have a special place in the vegetable garden because they are host to nitrogen fixing bacteria and so can add fertility to the soil as they grow. This won’t happen unless the right type of bacteria is present in the soil though, so if you haven’t grown peas within the last five years you should inoculate the seed with a suitable strain of inoculant.

The real flavor of Snap peas comes through best when they are eaten raw and this is how almost all of ours get eaten. My children will eat them straight from the vine all day long and few pods actually make it as far as the kitchen (their friends have been known to strip a planting of all pods of any significant size). They are also good when very lightly steamed, but don’t cook them for more than a couple of minutes, or they may turn to mush.

Tips on growing great peas
Air Temperature: Peas thrive in cool weather and don’t like heat, with 60-75˚ F being optimal. They are fully hardy and the first planting can be sown directly into the garden in early spring, a month before the last frost date.

Soil Temperature: The soil doesn’t even have to be very warm, as they will germinate (if rather slowly) at temperatures as low as 40˚ F.

Succession Planting: It is a good idea to make several succession plantings about 3 weeks apart, to ensure an abundant supply of pods until the weather gets too warm.

Weeding: The established plants don’t require much care. Weeds can be a problem for the young seedlings, but they soon outgrow and overshadow any weeds.

Watering: They do need regular moisture, but in early spring there is usually plenty in the soil and you rarely need to water.

Getting set up
The original Sugar Snap is a pole variety and must have a tall support structure for good growth (hog wire fence works well). If it isn’t tall enough they will eventually run out of climbing room and flop over (when my dad first grew them in England they went right over the top of his 6 foot high wall and started supplying his neighbor with pods).

It is a good idea to set up your supports before you plant, as it’s easy to damage the fragile seedlings. If you don’t want to deal with such a tall plant there are now bush varieties, such as Sugar Ann.

It is easier to provide support for the plants when they are growing in rows, so they are commonly planted in double offset rows with 3” between the plants and 6” between the rows. If you need more than one double row, then leave 24” between the pairs of rows.

You can also wrap hog wire fence into a cylinder and plant in a circle around it (this looks quite ornamental when fully covered, though not for long).

Established plants grow vigorously and quickly produce a wall of foliage 6 to 8 feet high, which makes an attractive (though temporary) screen.

Pests to watch out for
The biggest obstacle to growing Snap Peas is getting them established. It’s not that they are hard to germinate (this is easy) but rather that birds like to eat the succulent green parts and often pull the emerging seedlings out of the ground. The best way to prevent this is to cover the whole bed with netting.

Mice can sometimes be a problem too, as they sometimes dig and eat the seed before it has even germinated. If they are a problem you might have to start your plants indoors, though they dislike transplanting, so must be grown in individual cell packs (and not kept indoors for too long).

Ready to harvest!
The pods mature quickly after pollination and you need to check and harvest the plants regularly (every day or so). Harvest the pods when they are fat and round and sweet to taste. Don’t harvest too early or they won’t be as good as they can be.

It is important to pick all of the pods as they size up, if you leave some on the vine the seed will mature and production may decline (if this happens save the seed for planting next year). In cool weather, a well managed planting may yield for 6 weeks or more, though if the weather turns hot it may be as short as 2 weeks.

Smart Gardener makes it easy to grow peas, and more! We help you every step of the way from selecting seeds and preparing your garden, to sending you weekly reminders of garden tasks to keep your plants healthy and happy!

Making your own fertilizer mix

Image: soil mix with scoop. Photo source: Neslihan Gunaydin, Unsplash

Making your own fertilizer mix has several advantages over buying a pre-packaged mix. That’s why it’s a basic component of Smart Gardener’s approach to organic gardening.

Here’s a couple reasons why we like it so much:

1) Simplicity. It makes the whole question of “Which fertilizer do I use?” much simpler. It reduces the amount of boxes, bags and bottles of lots of different fertilizers you have to buy and store.

2) Less costly. It can save you quite a bit of money (as much as 50%), which you can then use for other gardening purposes.

3) Easy. It doesn’t take much time or effort to mix the various materials together, though it can be a bit dusty and the bulk bags are fairly heavy (they usually weigh 50 lb).

4) More flexibility. You can alter the recipe to better suit individual crops and can avoid materials you don’t like (for ecological, ethical or other reasons).

5) Buying bulk and sharing. If you buy the ingredients in the large bags. it’s great for community or school gardens, as well as sharing with neighbors or friends.

Where to buy
Generally the cheapest place to buy your materials is from a farm supply or feed store (a rule of thumb says that it’s cheaper to use materials sold as animal feed rather than fertilizer). If you don’t have a local feed store or farm supply,  then your next option is a garden center. These are set up for home gardeners so everything is in one place and it’s easy to compare materials and prices.

Choosing the ingredients
A complete fertilizer mix will include a source of each of the primary nutrients: nitrogen, phosphorus and potassium, as well as the secondary nutrients (calcium, magnesium and sulfur) and trace elements. The materials you choose depends not only on their nutrient content, but whether your priority is cost, organic purity (the cheaper amendments are mostly waste products from commercial agriculture and may contain pesticide residues or GMO’s) or ethical concerns (we won’t use products from industrial livestock raising).

How much to buy
Some ingredients are used in much greater quantities than others, so if you simply buy one sack of each material you will run out of one ingredient before any of the others. The next time you go to buy ingredients, you will only need to buy those that are in short supply.

For convenience you can mix all of the ingredients at once and store it in a cool dry place (though it’s probably best not to store the mix for too long). You can also store them separately and mix as needed. We use the white 5 gallon plastic pails with lids.

The recipe uses proportional quantities so you can use any container (whether a gallon pail or a teaspoon) to make as much as you need. I usually put all of the separate ingredients into a wheelbarrow and mix them thoroughly with a shovel (wear a dust mask as some of the finer ingredients are pretty dusty). It’s not a bad idea to do this over a clean hard surface, so you can recover anything you spill. For smaller quantities, a gardening bucket or pail works well.

I store the prepared mix in a plastic bin, though you could also use the paper sack the amendments came in. Some of these amendments are edible, so if you have rodent problems you will have to store them in a secure metal or plastic container, otherwise they may get eaten (and you may have a rodent explosion). They also need to be kept dry of course, otherwise they will rot.

Standard Mix
This is a mix of various amendments intended to supply all of the nutrients plants may require. It is usually incorporated into the soil prior to planting. The mix consists of:

4 parts cottonseed meal (this is high in nitrogen and relatively inexpensive)

2 parts colloidal phosphate or bone meal (for phosphorus)

2 parts wood ash or 3 parts greensand or granite dust (for potassium)

1 part dolomitic limestone (to balance pH and add calcium and magnesium)

1 part kelp meal (for trace elements)

Mix these together thoroughly. You can do this all at once, or you can store them separately and mix as needed.

Optional extra
2 parts of sifted worm castings (This adds microorganisms and micronutrients). I prefer to store this separately and add shortly before using.

Custom mixes
You don’t have to use the recipe above, you can customize it to better suit the crop you are growing. Conventional wisdom recommends giving additional nitrogen to leaf crops, potassium to root crops and phosphorus to seed or fruit crops, so you could add extra of these as required.


How do I prepare my garden for planting?

Image: close up of blue spade in garden bed. Photo source: Markus Spiske, UnsplashIf you’re like me, when the first warm days of spring arrive, you can’t wait to get out into the garden and start planting. It means winter is finally over and the gardening season has begun. You’ve been looking at seed catalogs for months and have plenty of ideas you’re just waiting to try. However, before you plant anything you need to get the soil ready.

Don’t be intimidated
This can be quite a bit of physical work, but luckily it is pretty straightforward and doesn’t take a lot of explanation. It helps to do it methodically though, so I’ll go through the steps here. And, while it may feel overwhelming to considering tackling a large garden space, keep in mind you don’t need to do the bed preparation for your entire garden at one time. You can easily do each bed as you need the space for planting, and leave the rest for another time. Start small to keep it manageable.

When to start
Just because it is a beautiful day doesn’t mean you can just go out into the garden and get to work on the beds. I know it’s tempting, especially after a long, wet winter, but digging very wet soil can damage its structure and cause long-term harm (not to mention being harder to dig).

To determine whether your soil has the right moisture content, you can do a rough check by lightly squeezing a handful of soil into a ball and dropping it from approximately waist height. If it doesn’t break up when it hits the ground it is probably too wet to dig (you have to take into account that a sandy soil breaks up more easily than a clay one).

Image of a woman working in a garden with a shovel, surrounded by plants.Another indicator of excessive wetness is when you walk on the soil and leave shiny footprints where water was squeezed from the soil. If your garden tends to stay wet every spring, it helps to use raised beds, as they drain and warm up faster than flat areas.

One very wet spring I was so desperate to get outside and get planting I covered some of my raised beds with plastic sheet to prevent them absorbing any more rain. This actually worked quite well, though such extremes aren’t usually necessary.

Clearing the space
If the soil is dry enough to work, you can start bed preparation by removing all of the surface vegetation. If there are only a few weeds or dead crops, it only takes a few minutes to loosen them with a fork and pull them out. If you have been growing a cover crop over the winter, removing it is a much bigger job. The quickest and easiest way to do this is to skim off the above ground parts with a sharp flat spade and compost them (cut right down at soil level, to sever the top growth but leave the roots in the soil). You could also dig the cover crop into the soil, but it will need a couple of weeks to break down before you can plant into it. This means you will have to prepare beds a couple of weeks before you intend to plant.

Image of a person holding their two hands out filled with dark, rich soil.Amending the Soil
Now that you have your garden bed cleared, it’s the perfect time to add any soil amendments you need. Typically, I add a couple of inches of compost and some standard fertilizer mix. If you know your soil’s pH balance if off, this is also a good time to add some ground limestone for acidic soil, or some pine sawdust for alkaline soils.

These are simply scattered on to the soil surface and then incorporated into the soil. If the soil is already in good shape, you can simply dig them into the top few inches of soil with a fork. If it isn’t so good then single digging works better. If the soil is very poor or compacted you may have to resort to double digging (usually you only need to do this once though).

Once you have your amendments thoroughly incorporated, all that remains is to break up any large soil clods with a fork and then shape the bed with a rake. It is then ready for sowing or planting and your garden season has officially begun.

Don’t feed the birds

There are few things more frustrating than preparing, planting and pampering a bed of peas or beans and then discovering that the newly germinated seedlings have all been wiped out by birds.

In most places birds are only a significant problem in spring when they seem to relish the abundant succulent green seedlings, but in my garden quail can be a problem anytime. In winter they go for the Brassicas, in summer they like any succulent greens, and in fall they eat newly sown, or emerging, cover crops. I’ve learned the hard way if I leave a seedbed unprotected I am pretty much wasting my time, as I will be lucky to harvest anything from it.

Tips on how to protect your plants:

Easy: The easiest method to keep birds away is to use scare tactics such as flashing tape, hanging old CDs, scarecrows, and predator balloons. The problem with these is that birds will eventually get used to them and start to ignore them, though they may work long enough for your planting to grow out of its most vulnerable stage.

Functional: The usual solution to serious bird predation is plastic netting. This is awkward to handle and put up (it’s an extra step after planting that you don’t need), and somewhat hazardous to wildlife (I have released several tangled snakes) but in these circumstances it is a necessary evil. I usually support the netting on hoops made from lengths of discarded ½” polyethylene irrigation pipe, weighted down at the edges with wood or soil. It’s not particularly elegant, but its quick and it works.

Extreme: In the most extreme cases you might decide to cage the whole garden (especially if you are also plagued by rabbits, deer, squirrels, or raccoons). The simplest and cheapest way to do this is to put an 8 foot tall chicken wire fence around the garden and make a roof out of plastic bird netting.

Spring Vegetables

Image of seedlings in pots. Photo Source: Francesco Gallarotti, UnsplashSo you’ve got your soil ready, it’s finally warm enough, and now you’re thinking about what to plant. It’s tempting to start planting all those great seeds you bought over the winter, but it’s best to take a moment and consider what weather conditions each plant needs to germinate and thrive. Each plant has an appropriate time to be planted, and it’s important to be aware of which plants can go out at what time.

The vegetables that grow well in spring all originated in temperate climates and prefer cool (50-75˚ F) growing conditions. When you first plant your spring crops, the soil and air are cool and days are fairly short, so crops germinate and grow slowly. As spring progresses the days lengthen and the weather gradually warms, until by the time most crops are ready to harvest it may be warm most of the time. Fall has cool weather too, but there the reverse is true, conditions are warm for seed germination and growth (and pest activity), while maturation takes place in cooler weather.

When to plant
Blue spade in garden bed. Photo source: Markus Spiske, UnsplashIt is important to get your spring crops into the ground as early as possible, so they have enough time to grow and mature before the long, warm days of early summer cause them to bolt or develop bitter or pungent flavors. Fortunately cool weather crops aren’t perturbed by minor cold snaps, so planting them early isn’t a big problem. If it is cold they will just sit and wait until the weather warms up enough for growth.

The hardiest crops can be planted as soon as the ground is suitable for making beds in spring, which may be 4 to 8 weeks before the last frost date. These plants include: leek, onion, parsley, pea, spinach, and shallot.

The slightly less hardy crops can be sown 2 to 4 weeks before the last frost date. These include: lettuce, cilantro, mustard, and radish.

The rest of the spring crops are sown a couple of weeks before last frost date. These include: beet, carrot, broccoli, cabbage, chard, kale, and potato.


Smart Gardener makes it easy
We show you quickly and easily when it’s the right time to start your seeds indoors or outdoors, based on your region. Just check the Overview tab in the variety descriptions, and you’ll see when to start your seeds, transplant your starts, and harvest your vegetables. The top lines are for spring/summer crops, and the bottom lines are for fall/winter. Easy as can be!

Planting Overview showing sowing guide

Early spring planting tips

Image of three seedlings on wooden board. Photo source: Daniel Hjalmarsson, UnsplashYou’ve already selected the area for your garden, started your seedlings, tended your soil, and mapped out your garden bed. All that’s left to do now is get planting. So, when is the right time to transplant your beautiful starts? Ideally, the spring growing season starts when the day length gets over 10 hours (which seems to be a minimum for plant growth) and the daytime temperature regularly reaches into the 50s or 60s. But it’s a bit more complicated that simply checking the air temperature and daylight hours.

Soil warmth
Close up of hands holding a seedling in dirt.At this point the only remaining obstacle to significant plant growth is cold soil, as this warms up much more slowly than air. Fortunately you can warm the soil quite easily by covering it with polyethylene sheet for 2 to 3 weeks. Black colored sheet can raise the temperature by 10˚ F, while clear sheet can raise it by as much as 15˚ F. If you plan on using a tunnel cloche to protect your plants, you can simply put this on 3 weeks early and it will warm up the soil for you. These methods will also help the soil to dry out, which is good for soil preparation and planting. It should go without saying that if you had mulch on the bed over the winter, this should be removed several weeks before planting, as it insulates the soil and prevents it from warming up.

Temperature is temperamental
Spring weather varies enormously from year to year and is only predictable in its unpredictability. At Smartgardener we use the average date of last frost to time our planting, because it gives us a practical way to estimate planting times for the whole country. This works well, but it is important to understand that the average date of last frost is just that, an average and that in any given year a frost may come several weeks earlier or several weeks later.

Image of broccoli florets in a basket.

The first spring crops (kale, broccoli, snow peas) are perfectly hardy and aren’t bothered by low temperatures, they will just grow very slowly until warmer weather arrives. The warm weather crops (tomato, pepper, squash) are more vulnerable however, as they stop growing completely and can become susceptible to rot and pests (in some cases they may even be permanently damaged).

It seems like every year I plant my warm weather transplants in sunny weather and within a few days its turns cold and wet. The most urgent need is to protect them from any frost, which could kill them before they even get going. The plants are pretty small at this point and so are easy to cover with frost blankets or a few inches of loose mulch (and maybe a bucket for extra insurance).

Building for warmth
Image of a child water plants in a garden bed under a cloth covering.Of course it isn’t enough to just keep the plants alive, you also want to keep them growing vigorously and you can do this by using tunnel cloches (these consist of a simple series of hoops covered in clear polyethylene sheet). The temperature inside one of these may be 20 degrees warmer than outside and it can really speed up plant growth. Being able to protect and pamper your plants in this way allows you to plant earlier and have faster growth. Do it well and you can be eating tomatoes in early June, rather than early August (you might even get into a friendly competition with yourself to get ripe tomatoes earlier every year). Tunnel cloches heat up so well on sunny days, they need to be well ventilated to prevent them overheating and cooking the plants inside.

A dual use tunnel cloche for tomatoes can be made from a piece of hog wire, bent into an arch and covered with polyethylene sheet. When the weather warms up you remove the plastic, but leave the hog wire in place to act as a support for the plants.

Where to Put the Vegetable Garden

Image: selection of shovels and a pitchfork in grass. Photo source: Dylan Nolte, UnsplashIf you are completely new to vegetable gardening, one of the first things you need to think about is where to put the garden.

In a small garden you usually don’t have many options. It has to go where there is room. Don’t make the mistake of putting it where it won’t work though. If the best place is already occupied by an ornamental bed or a garden shed, it may be necessary to rearrange things to make room for the vegetables. In some situations you might have to remove sources of shade, such as a tree, in order to get enough sunlight.

In a large garden you’ll have many more options. If you have several choices you should try to take advantage of any favorable microclimate, such as a south facing slope. Ideally the vegetable garden should be fairly low down on a slope to avoid high winds and to get better soil with more moisture. However it should not be so low that it is in a frost pocket. In a dry climate you might put the vegetable garden in any area with naturally moist soil. A flat area often isn’t as warm as a south facing slope, but it is generally easier to work with.

There are certain conditions that all food gardens must meet in order to be productive. Consider the following before you start digging:

Image of a watering can watering plants in a garden. Photo source: Markus Spiske, Unsplash

The most important factor in growing a garden is sunlight. More sun means more plant growth. In fact, the majority of crop plants need at least 6 hours of direct sunlight a day to grow well. So your first objective is to put the vegetable patch where it will get the most sun.

A fertile soil is also a big help, but it is less important than sun because you have the power to improve the soil through your gardening activities.

Good drainage is important because plants won’t grow in waterlogged soil. This is particularly important in spring because you should never dig wet soil (it will damage the soil’s structure). And waiting for the soil to dry out can cause delays (wet soil also warms up more slowly than dry soil).

If your garden is exposed to strong winds, you will need to think about shelter. Strong winds can batter plants, cool winds can chill them and dry winds can increase evaporation. If there is no natural shelter you will have to think about a windbreak (without creating shade however).

You should never put your vegetable beds on the north side of tall objects such as buildings, walls, trees or shrubs where they will get little sun. You should also keep them well away from any trees or shrubs, as their creeping roots will move into the fertile and well watered soil and extract most of their available nutrients (this would drastically reduce your crop plant growth).

A graphic showing a garden's optimal orientation to the sun

Consider the proximity to the house. The closer the food garden is to the kitchen the more you will use it. Ideally the garden should be within 100 feet of your kitchen door so it is easy to nip outside and harvest while cooking. If it is further away you tend to limit your trips out there , so the harvest becomes more sporadic. Someone once estimated that the harvest declined by 30% when the garden was over 100 feet away. A garden that is close to the house gets tended more conscientiously, not only because it is more convenient, but because it is so visible. You make more effort to keep it looking good because otherwise it would be embarrassing every time someone came to visit.

Finally it’s nice if the vegetable garden is in its own area and isn’t on the way to somewhere else. If it is right in the center of a play or entertainment area then plants may get damaged by passing children, dogs and wheelbarrows; and those tempting ripe tomatoes will keep disappearing.

Image of a garden layout showing shade area creates a Smart Garden Plan for you which automatically and optimally orients all your plants in relation to the sun – so you can get out into the garden!