Q. On the back of packets of vegetable seeds, it gives a maturity date (i.e . 70-75 days). If the seeds are started early indoors (say, three weeks before last frost), does this affect the maturity date? Should I go by the date of sowing, the date of germination or the date that I transplant the seedlings outside to determine when the vegetables should be harvested? My problem is that I need to reuse the small space that I have for spring, summer and autumn crops, so I need to be able to estimate when to start the next crop. --D.W., Ronkonkoma, NY
A. The dates to use are always a guesstimate as well as gamble, art and science. The weather has a lot to do with it, too. Although starting seeds indoors allows for more reliable germination, it's also a bit of a stress on the plants to be grown indoors without real sunshine--their growth slows during the acclimatization process and then transplanting takes its toll, too. So although there is a time gain, it is not always as much as we would hope and certainly not as much as the lead time involved from seeding to setting out.
In some cases, the real gain is that the plants are set into the garden on a schedule that optimizes the growing conditions. That is, early broccoli can be grown to maturity while the temperatures are still cool, or tomatoes can be set out when the soil has warmed--most tomato yield dates are calculated from when the plants are set out. Most long season plants also have a fairly wide "window" during which they can be transplanted. Tomatoes for instance can be set out as early as four weeks or as late as eight to ten weeks after seeding assuming the soil is warm. Lettuce, as a short-term grower, would have a much narrower window because it matures so quickly. In my experience, most of the midseason shorter-term growers such as bush beans or Swiss chard can be started from seed at almost any time and will be mature according to the time frame on the label. Swiss chard, however, can be harvested prior to that, since it can be handled as a cut and come again crop. This means that the real problem is planning the fall garden. To do that, count backwards from the maturity date and add about ten days to account for the shortening daylight--this will tell you approximately when you need to plant. It always seems that it works out somehow, but there's nothing wrong with planting a patch of soil-building green manure or allowing a section to sit fallow for several weeks, or planting a quick-growing patch of basil or something else minor to fill the time. Bush beans take about 45 days and are a traditional filler.
So although I have not given you specifics, I hope this helps you time your planning. This is something each gardener has to decide based on personal preferences and gardening techniques. Keeping a notebook can help you build on your experience from year to year, too.
--National Gardening Association
