Since we’re on seed talk, let’s chat about seed sowing depth! This is an important topic to know about if you’re a from seed gardener.
The overwhelming bulk of garden seeds are sowed underneath the soil. The sowing depth isn’t always communicated on the seed packet, but it is somewhat important. The best rule of thumb is to sow seeds around two times the width of the seed. So, for example, if your seed is approximately 1/16″ wide, you would sow it around 1/8″ beneath the soil. A very tiny seed would just barely be covered by any soil. You can choose to sow in a small hole, or just cover them with additional soil.
There is a bit of flexibility to this and absolutely no need to be neurotic about it! Just don’t go smashing them deep into the soil and you’ll be fine. (Except big seeds like peas and squash! Often these are sowed deep, again about twice the width of the seed!)
Some seeds are rather particular, in that they don’t like to be covered by soil at all. When this is called for, we have found this vitally important for some types of seed, much more flexible in others. For these, simply place the seed on top of the soil, no need to cover them or follow the above recommendations. For the seeds that it is critically important to treat this way, we have found this always well defined on the seed packet’s instructions.
We let this subject intimidate us for way too long! We remind you again and again that every seed packet comes with its very own manual for growing that plant! Sure, you will develop expertise over time. But, if you’re trying to figure out all these “complicated rules” about gardening…just read the seed packet! If it doesn’t say anything specific about sowing depth, assume you use the rule of thumb!