So the seed pack says 85 days....

is that from planting to first harvest?

sprouting to plant maturity

What's it all about , alfie?

It is a general and vague suggestion of how long it might take for one variety of a particular vegetable to reach maturity relative to another variety of the same vegetable from the same seed packager.

Thus one seed company might say that fourth of july tomatoes will mature 54 days from transplant, another might indicate 45 days from blossom set, and yet another might suggest 92 days from germination.

You have to check with each individual seed company to know for sure what they are talking about. But I have found that generally for plants that are grown from seedlings or nursery starts the numbers mean days to maturity from the date of planting out.

With direct sown seeds, the number usually means days to maturity from date that sprouts appear.

I have also found that the actual number of days to maturity can vary by 50% or more either way. Temperature, water, light, and soil conditions all have substantial impacts, but that in general, if one type of vegetable is "late" or "early" relative to the number of days to maturity on the seed packet, generally everything in garden is similarly late or early.

So, to summarize, the number on the seed packet doesn't really mean much except "heres a number so that you can compare this variety of beans to another variety of beans, and maybe a lower number is better...or not".

Thanks Ctdahle!

DTM is highly subjective. I use nothing on my own seed packets. If I can grow it in NH, maybe you can too where you live.

If you are trying to get fall crops to mature- double the days to harvest since the growth is slowed in cooler temps. The days to maturity are measured in optimum conditions, not October. It makes fall crops much more difficult to harvest in the north than you would think by looking at a calendar and seed catalog!