Whether a Master Gardener or just getting started, sometimes it's good to go back and review the basics. Eric will be planting some annuals and wants to start by talking about soil preparation. This is a step you cannot skip. A lot of gardeners just take their spade, throw it into some hard soil and put the plant in. You shouldn't be shocked when the plant doesn't make it. When looking at the make up of the soil, we think of it in thirds. A third for water holding capacity, a third for air and a third for the inert material in the soil. If we have too much of one or not enough of another you will have problems with the soil being either too wet or too dry. Plants need a perfect environment to thrive. But, it's not as hard as it sounds to make sure we have enough organic or composted material. In the patch Eric will be working he has added compost material. First clear the area, then till it up. If you don't have a tiller you can use a shovel. But the end result, what we want is something that is very loose. This is where you get the air space in the soil along with little rock, pebbles and sand. This is very important if we don't have enough air space you'll end up with compacted soil, the roots won't be able to integrate into the soil, creating all sorts of problems. It's also important not to plant into something that's dry. Dry soil will suck the water out of the root ball, it will dry your plant out.
Eric has some Petunias and Marigolds he is planting. He likes to buy his annuals on the smaller side, he doesn't want something completely packed out. There are reasons for that. If you buy an annual completely packed out it may be a slightly larger plant than the flat that's a little smaller but you will have circling roots, a tight compacted root ball. It will take a long time for the roots to integrate into the soil. If you do buy annuals that are very well rooted out what you want to do is break up the soil or root ball. That's a good idea whether perennials, woody ornamentals, especially with annuals. We want the roots to grow in all different directions into the nicely prepared bed. This plant has roots all along the edges, they've not been in the container long enough to start spiraling. Even so he breaks up the root ball just a little.
And as you plant, don't make the hole too deep, the plant shouldn't be too deep in the ground. Then run a little soil along the top of the root ball. That will protect the top from drying out. Then lightly and gently move the soil around the edges of the plant. Then when everything is planted it's important to water everything in very well, then put mulch down. Most mulch today has a weed preventer built in which keeps weeds from competing with the annuals and provides a much better chance for survival.