when to start seed

A Way to Garden when to start seed calculator

NEED HELP remembering when it’s safe and smart to start your first spring sowings of vegetable, flower and herb seeds indoors and out? This tool calculates when. Begin by entering your final spring frost date on the top right of the chart below. (Don’t know? Search by ZIP Code with the tool at this link.)

The chart dates below suggest earliest springtime sowings, but there is no hard-and-fast rule whether lettuce needs 4 or 6 weeks indoors—or if you never give it a headstart, but simply direct-sow. This is my best guidance, not doctrine; that’s why my website is “A Way to Garden,” not “The Way to Garden.”

Note: Reemay or other protective row covers can “cheat” the earliest transplant dates by as much as 2 weeks, especially helpful with tender things like melons (or insect-prone brassicas and cucurbits).

Many crops (salads, carrots, beets, bush beans, cilantro…) are best sown in succession, a small amount every 2 weeks, starting at the chart date. In some climates, a later sowing timed for fall or winter harvest (e.g., Brussels sprouts) may do better than a spring one, or you can get a second sowing in of peas that you sowed in spring, then pulled.

I’ve added a list of how-to story links below, including some on stashing your harvest. Again: Start by entering your final spring frost date below (mine’s about mid-May). You can print your results using the button under the chart (it will be about 5 pages).

a spring garden calculator

how to sow, harvest and store vegetables

seed-starting gear i use for best results

31eQ6QoZ18L. AC  image SUNBLASTER LED STRIP LIGHTS: I use T5-HO fluorescent lights or as those units need replacing, newer and more efficient LEDs such as the strip lights by Sunblaster (available in different lengths).
71wAJpsl29L. SL1500  image SOLO 2-LITER ONE-HAND PRESSURE SPRAYER: I mostly bottom-water seedlings, but during germination and when seedlings are tiny I mist them with this handy sprayer.
61xTd1cYk4L. SL1500  image 10-GALLON TRUG FOR SOIL MIXING: A 10-gallon trug or larger plastic bin is a great vessel for slightly moistening germinating mix before filling flats.
71EU5Da9cDL. SL1500  image SURGE PROTECTOR TIMER: No more one timer per growlight! With 8 outlets, program multiple lights to turn on and off for the required hours per day.
9227 image JOHNNY'S 512 MIX: I've ordered this for germinating purposes for years. Has organic nutrients (fishmeal, not chemicals) added. Works for soil-blocking, too.
81ehrs+WmYL. SL1300  image SEEDLING GERMINATING MAT: I use single tray-sized mats (approx. 8.5x18.5"), but mats also come in double-wide or double-long (for 2 trays), and up to 5-foot-long pro versions.
31oHiHnWANL image LADBROOKE SOIL BLOCKERS: Many experts swear by soil blocking (as opposed to sowing in cells or open flats without blocks). The tools for making blocks, in various sizes. Note: The mix you use must be rated for blocking.
gloves image NITRILE-COATED GARDEN GLOVES: I like mine black, and by Atlas or Bellingham. I eventually poke through the right hand middle finger from digging with my hands...but other than that they'd last a long time.
71UyXTCuE2L. SL1100  image PULLEY HARDWARE FOR GROWLIGHT: To hang and adjust your hood, you'll need to rig S-hooks and chain, or even easier pulley with store-bought hardware. (Shown: Vivosun brand.)

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