Direct sowing cool season crops

Once the snow has melted, and the soil is workable (that is, it is neither frozen, cold, or very wet), you may direct sow cool season crops.  These plants tolerate overnight temperatures that hover around the freezing mark, and even a touch of frost; they prefer the cool temperatures of spring and fall rather than the heat of summer, during which they may bolt (go to seed too quickly).

Refer to the seed package to see how many weeks prior to the last frost that you may sow the seeds.  The package may also list an ideal soil temperature.  You may choose to place row covers over the area that you are planting to expedite the warming of the soil and protect your plants from occasional cold nights.

The following plants are quite hardy, and can tolerate a soil temperature of around 5°C:

  • Leeks
  • Peas
  • Radishes
  • Spinach, lettuce, collard greens, kale, kohlrabi, and other greens
  • Sunflowers
  • Turnip and rutabaga

The following plants are also quite hardy, though they prefer a slightly warmer soil temperature of around 10°C:

  • Broccoli (shown above), Brussels sprouts, cauliflower, and cabbage
  • Beets
  • Carrots
  • Chard
  • Kohlrabi
  • Onion sets
  • Potatoes
  • Parsnips

Edible perennials

Most edible garden plants are annuals; that is, they must be planted from seed each year.  Perennials are plants that remain productive year after year.  They may go dormant in the winter, and re-emerge in the spring.

Perennials often need a few seasons to mature before they begin to produce.  Once they are established, they may be prone to spread to the point that they become invasive, so be sure to carefully plan their locations.  It’s a good idea to keep perennials together so that you don’t have to cultivate in and around them each year when you sow your annuals.

Here is a list of edible perennials:

  • Asparagus
  • Bamboo roots
  • Berry bushes, such as raspberries and blueberries
  • Bunching / Welsh onions
  • Chives
  • Collard greens
  • Egyptian onions
  • Fruit trees
  • Globe artichokes
  • Horseradish
  • Jerusalem artichoke / sunchokes (flowers shown above)
  • Kale
  • Lemon balm
  • Lovage
  • Mint
  • Oregano
  • Radicchio (technically a hardy biennial)
  • Rosemary
  • Rhubarb
  • Sage
  • Sorrel
  • Strawberries
  • Wild leeks / ramps

The great zupumpkin!

In one of my first small gardens, I planted a pumpkin plant and a zucchini plant next to each other.  I didn’t save any of their seeds, but the next year, when I spotted a pumpkin plant coming up from the compost, I let it grow.  It started out looking like a bit like an elongated pumpkin or some sort of squash.  Then it ripened to the above specimen, which was christened the zupumpkin.

Cross-pollination

Cross-pollination occurs when an insect or the wind carries pollen from one variety of plant to another.  The resulting seed, when planted, sprouts a hybrid of its parents.  Since zucchini and pumpkins are both varieties of the same species, they can create the zupumkin (or zumption or pumcchini–your choice) but a cucumber and squash can’t procreate because they’re different species.

Cross-pollination does not affect the current year’s crop, but rather the next year–with one exception: corn.  If the pollen from the tassels of one variety of corn are blown into the silks from another variety, the cob that develops is a hybrid.

Self-pollinating plants

Vegetables like beans, peas, peanuts, eggplant, peppers, lettuce, and tomatoes are self-pollinating. Their seeds will produce plants like the parent, but insects will occasionally cross them, so if you want to be absolutely certain that your seeds will grow true to type, plant each variety at least 10 feet apart.

Insect- and wind-pollinated plants

Vegetables that are pollinated by insects or wind need to be separated by variety, and grown a distance apart (the distance varies with each type of plant).   To ensure that your seeds grow true to type, grow one variety of each type, or separate the different varieties.

Vegetables that willingly cross-breed

The following plants or plant families are prone to cross-pollination.  If you are planting them with the intention of keeping their seeds, keep varieties well separated.

  • Beets and Swiss chard
  • Cauliflower, cabbage, kale, Brussels sprouts, kale, collard greens, and broccoli
  • Corn
  • Cucumbers
  • Honeydew, cantaloupe, and other melons, excluding watermelons
  • Peppers (hot and sweet)
  • Squash (some varieties)
  • Zucchini and pumpkins