How Gardens Work…
WHEN TO PLANT
Timing is Everything
Timing is important mainly because of temperature. We don’t all live in the same climate zone. So, not everybody, everywhere, can plant everything on the same day. One thing to consider is the type of weather a particular plant likes.
For example, some plants like beets and potatoes really like the cold and do well. They are called “cool weather” vegetables or plants. Other plants like tomatoes and cucumbers are warm weather lovers and don’t even like a slight chill. These are called “warm weather” vegetables or plants. But that’s not all to think about. If you want to plant a “warm weather” crop, how do you know when it is “warm” enough? If you live in Southern California you can plant pretty much all year-round with the crop you choose depending upon the hours of sunlight it needs per day rather than upon temperature. But if you live in Northern California you might not be able to plant things until May or June.
So, how do you know when it’s safe to start planting warm weather plants? There is a frost-free date in the spring that tells you when it’s safe to start planting the tender “warm weather” vegetables or plants that do not like frost. There is also a first-frost date for fall that tells you when it’s going to get too cold them to grow well. The number of days between these two is called the growing season. The USDA has created a “zone” map that gives a special number to different “zones” or areas with similar growing conditions… where a plant will be happy and “hardy.” This is called the “Plant Hardiness Zone map.” Oftentimes you will see that a plant is suited for more than one zone with a list of each zone number that a plant will be most comfortable.
WARM WEATHER CROPS
Warm-weather crops are not frost-tolerant and should not be planted outdoors until all danger of frost has passed. One way to get a jump start planting heat-loving vegetables is to start seeds indoors or buy seedlings and set them into the garden as transplants. Tomatoes and peppers need a long growing season and are best grown from transplants in short-season northern climates. Tomato transplants should be put in the garden one to two weeks after the last frost. Those with the astericks (*) in this column are good choices for container gardens.
COOL WEATHER CROPS
Those with the astericks (*) in this column can be hurt by frost, but cannot grow when temperatures rise above 70 degrees either! Many brassicas, alliums, root crops like beets and radishes, peas and leafy greens like leaf lettuces and spinach grow best in cool weather. Brassicas are not only frost-tolerant, but a light frost often improves their flavour. Broccoli, cauliflower and the hardier cabbages can even take a hard freeze. Brussels sprouts are another late-season winner and taste better after a hard frost. Sow them four months before first frost.
A few crops do well in all seasons without too much trouble. Swiss chard grows well in warm or cool weather. Kale is so hardy it will even come up in the snow!It produces greens throughout the summer but will also withstand a mild frost. Collard greens love hot, as well as cool, weather.But just because some veggies do not like heat, there are ways to get around the hot summer weather. Spinach and lettuce, for example, don’t germinate well in hot weather, so you can start seeds indoors or sow them more thickly. Provide shade for young cool-weather seedlings until temperatures cool down. Plant lettuce under a tree or on a patio that does not get direct sun. Remember to water the soil before you plant, and plant – or transplant – late in the day. FROST DATES So, how do you know when it’s safe to start planting warm weather plants? There is a frost-free date in the spring that tells you when it’s safe to start planting the tender “warm weather” vegetables or plants that do not like frost. There is also a first-frost date for fall that tells you when it’s going to get too cold them to grow well. The number of days between these two is called the growing season. One is the actual frost-free dates for the area where you live. To find out the last expected freeze date in your area, check the NOAA website. (NOAA stands for the National Oceanic and Atmospheric Administration.)
To read more about Chill hours, click here.