Easy Planting in May and June

From now through the end of June it’s time to plant the most straightforward and gardener-friendly crops of all--summer annuals. Beans, corn, squash, zinnias, and sunflowers have been grown in North America for thousands of years. You can plant their big, easy-to-handle seeds straight into the ground once frost is over and the soil is warm. Many summer flowers like cosmos, coreopsis, and marigolds thrive in the same conditions.

These crops were perfected by Native farmers who used a digging stick and a hoe--no tractor, no plow, no greenhouse, not even a spade. They don't need a perfect seedbed. What they do need is organic matter. They were originally grown in forest clearings, in soil created by centuries of fallen leaves. You can give them a great start by working compost into the top 2’” of soil.

All of the summer annuals like warmth and organic matter, but each has its own niche. Rather than get into endless detail, I've highlighted three important points for each vegetable

1. What unique strength it has
2. What it needs most from you
3. What's the most common problem to watch for

Beans are renowned for their ability to enrich the soil. Colonies of special bacteria in their roots are able to use nitrogen from the air as a food for the plant. But roots can't climb out of the soil to access that air--it has to be in the soil. Compacted, hard, mineral soil doesn't have spaces for air. Organic matter provides the meeting place of soil, air, and water where roots can make optimum growth and nitrogen-fixing bacteria can thrive. 

Give beans the best start by working in compost, or even old potting soil, crumbled leaves, or rice hulls to make air spaces. You can start breaking up deep compaction by using a broadfork or garden fork to loosen soil slightly. Just walk down the bed sticking in the fork every 8-12" and rocking it to let in air. If you've already planted, you can stick in the fork without rocking it, to make air holes 6"-8" away from your planted row.

Pitfalls to watch for are weeds and overheating. Use mulch or shallow hoeing to prevent weeds from competing with your beans. Beans are very sensitive to competition, and weeds will reduce your harvest substantially.
When the temperatures rise above 85, consider using shade cloth over your bean plants. Most beans prefer the same temperature range that humans do, and stop producing in very hot weather. It’s also worth seeking out heat-resistant varieties like Rattlesnake and King City Pink.

Corn uses sunlight in a way that's unusual in our gardens but common in tropical plants. It's called C-4 photosynthesis and it makes corn (and its cousin sorghum) extremely fast-growing in summer, right through the hottest weather.

Your job is to provide enough water and fertility to sustain that fast growth. It’s traditional to give corn a source of nitrogen in the furrow when planting. Manure, compost, alfalfa meal, fish emulsion, blood meal etc can be buried under the seeds. Make a deeper-than-normal furrow, put in the manure or whatever, then a layer of soil (easy to do by running a hoe along the edge). Then you can sprinkle your seeds into the furrow and cover. They should be 1" deep. Water well if needed, and be sure that your corn gets water as it grows. If the leaf tips turn brown or yellow, or the leaves get yellow streaks, or growth is slow, you probably need to water more. If water isn't available, thin the plants to avoid competition, and mulch well.

Corn's pitfall can be poor pollination, resulting in missing kernels. To prevent it, plant in blocks at least 5 feet square rather than in a single row. Corn pollen is spread by wind rather than insects. Planting in a cluster helps the pollen from the top tassels to fall onto the ears and pollinate them. It’s important to keep cucumber beetles from eating the silks for the same reason. (each strand of silk is a tube that pipes pollen down to a kernel. Once the kernel is pollinated, the silk starts to shrivel.) You can get sticky traps that attract the beetles with natural pheromones and capture them on the sticky surface without using pesticides.

Squashes superpower is their vigor. They shade the ground with big leaves that romp over the competition and out-compete most weeds. All types of squash, both zucchini and winter squash, love growing in a compost pile. This tells you three things: They like a lot of nutrients. They sprout best in warm, moist places. And they aren't picky about how "finished" the compost is. They will grow in stuff that's downright chunky and stinky, turn it into food, and grow like crazy.

When you're planting squash is the time to bury your kitchen waste, half-finished compost, rotten fruit, moldy dog food, or even dead gophers a foot (or 2 if it's dead or fishy) below the seeds or transplants. (More prosaically, use some feathermeal, alfalfa meal, or compost.)  They are great pioneer plants in new gardens--just cut down the weeds, put down cardboard or black plastic, and plant your squash in openings 4' apart. Mulching with pulled weeds or grass clippings will also give them a gradual nutrient boost.

Their weak points are pests and diseases. Inspect the underside of leaves for rows of oval brown eggs laid by the dreaded squash bug. Squish the eggs and coat the crown of the plant and the stalks with diatom dust. Surrounding your plants with nasturtiums, radishes, or other brassicas can deter squash bugs by masking their scent. In the south, borers are a big problem. One of the three main cultivated squash species, C. moschata, is much more resistant to borers than the other 2 species (C. pepo and C. maxima.) Butternut and Tromboncino which are both C. moschata.

As fall approaches, spray with compost tea, water with a bit of yogurt blended in, or other probiotic brews to prevent mildew. In fact, take measures against mildew whenever the humidity is high and temperatures are in the 70-85 range. Even if the daytime is dry, the onset of heavy dew in fall can be a problem.

Cucumbers, melons, and watermelons are members of the squash family from India, Persia, and Africa. Their vines are on a smaller scale than squash; still easy to grow and vigorous, but with smaller leaves and thinner stalks. They prefer a  more cultivated soil, finished compost, and mulch. Their smaller vines don't shade out weeds like the larger squashes do, so you need to control weeds with mulch or cultivation. They're still vines, though, and need water and fertility early in the season to fuel their growth. Like squash, they are prone to fungal diseases and should get probiotics. Cucumbers are best trellised to save space, make picking easier, and prevent downy mildew from sitting on damp soil. A thick mulch of straw and putting tiles, bricks, rocks, or other barriers under each melon will protect them from both damp and rodents.

Summer flowers and annual herbs like zinnias, coreopsis, sunflowers, basil, dill, and marigolds are not just the icing on the cake. They are a vital link between the garden and the rest of the world. Pollinators, pest-eating predators, birds, butterflies, and humans are all drawn into the garden when you add some flowers and herbs to each garden row. They are the garden's protectors.

Adapability is another strength. Flowers aren't heavy feeders, and don't have to ripen fruit. So you don't have to give them the best spots, or go to great lengths to please them.  I tend to put them in the corners of the bed, where conditions are likely to be less perfect than in the middle. If you have areas where tree roots intrude, there is a bit too much shade, or the soil is rocky, that's a good spot to try some flowers.

Your job is keep the sown areas moist until you see sprouts. Both flowers and herbs are sown very near the surface, so they can dry out easily. In summer heat and especially with any wind, that may mean watering twice a day, or covering until germination.

An early problem to look out for: overcrowding. Thin them to the recommended spacing. A clump of many seedlings in a tiny space will not produce more flowers--it will produce stunted plants that never make a show. Cutting the flowers (or removing dead ones) will provoke the plant to flower more. Here are some suggestions for using them:

I like small marigolds at the feet of tomatoes, and basil alongside peppers. Zinnias, taller marigolds, borage, or Glowing Embers cosmos make great accents at the ends of each vegetable beds. I find veggies often don't do well at the ends or corners where fertility or irrigation may not be as good; flowers cope with the drier, more compacted conditions just fine.

If you want the cheerfulness of sunflowers but can't find a place for large flowers, consider using them as light shade over beans, kale, lettuce, or other plants that dislike overheating. Or you can use them as a trellis for pole beans. Sow the sunflowers, let them get 8 inches tall, then sow the beans, one per sunflower. Plant in groups of three, so the sunflowers forma triangle  18" on a side. That way they make their own tripod support. The wandering, twining bean vines will hold them together.

Morning Glories are the loveliest way to hide an ugly view, dead stump, wall, or bare bank--the long vines cover the offending item, then cover themselves with magical blue trumpet flowers. At the opposite extreme, coreopsis and Sensation cosmos have such feathery leaves that you can see through them; they cast next to no shade.  I scatter them in the beds to add interest and attract beneficial insects--coreopsis among short plants, and cosmos with tall ones. Dill is similar. When they are an inch or two high, thin to the recommended spacing. Picking flowers will stimulate the plant to make more, so enjoy!