Planting seeds before a rain to save a step

It hasn't rained here for nearly a month, but it's supposed to tonight. I was thinking of doing some quick planting when I get home and let mother nature take care of the watering, is she usually sufficient for setting newly planted seeds?

How do I know if it's rained enough to equal what I would have wanted to put on the garden. Is rain water more effective at seed starting than tap water (even tap water stored in a barrel)?

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You're asking us how much water mother nature decides to dump on us any given day? – DA. May 24 '12 at 21:51
Nope. I'm asking whether it's OK to forgo the normal step of watering freshly planted seeds. Do you need me to clarify something? I'm not talking about day-to-day watering, just the watering you normally do when you set the seeds in the ground. – Peter Turner May 24 '12 at 21:53
The seeds will sprout with moisture. So, you can forgo it if you want to delay any sprouting. As for mother nature being 'sufficient' well it's entirely dependent on how much it rains. We can't predict that. – DA. May 24 '12 at 21:56
That's not the entire reason that one waters after planing seeds. – Peter Turner May 24 '12 at 21:58
Again, your question is entirely dependent on the amount of rain. Since that's not going to be predictable, I'll suggest you don't put all your trust in her and get the watering can out. – DA. May 24 '12 at 22:01

A rain gauge will tell you how much it rained. The local weather might also tell you how many inches of rain you received, though obviously they're measuring it from a different place than your garden.

However, with seed starting, you don't really have to worry about "deep watering" and applying "inches of water". You just need to keep the soil moist.

The simplest way to tell is just to use your finger. Stick your finger in the ground to the depth you planted the seeds, and see if it's moist. You probably want to check a couple of different places, especially if different parts of your garden get different amounts of sun.

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After I plant seed, I try to keep it moist until it germinates. This means watering every day that it doesn't rain, sometimes morning and evening if the day has been especially hot, sunny, and dry. If the weather is damp and overcast, even if it doesn't rain, I may skip watering if it looks like the ground where I planted is still moist.

So planting when there's rain in the forecast may save you a step.

With that said:

• If I thought there was a heavy rain coming, I might skip planting small seeds like lettuce to avoid having them washed away.
• If the predicted rain doesn't arrive, you'd best be out there watering!
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