Starting Seedlings in Styrofoam Cups

tomato seedlings in Styrofoam cups

tomato seedlings in Styrofoam cups

Starting Plants Indoors in Styrofoam Cups

As cold and wind and rain become outdoor companions this time of year, gardening may be the last thing on your mind. But with the help of some Styrofoam cups and a little soil mix, you can start many plants indoors, or on a covered patio or balcony. By the time spring arrives, or even before, you will have many flourishing plants ready to be transplanted into larger containers or into your garden.

Window Sill Perfect Spots for Planting in Styrofoam Cups

One of the best places for a winter nursery is the kitchen window sill. Plants situated on the window sill just above the kitchen sink will be noticed a dozen times a day or more. It will be difficult to ignore them or to deny them the minimal care they require.
Small cups (6-ounce size) are among the best containers for starting plants from seeds and cuttings, especially at this time of year. In winter, water is slow to evaporate from the soil. It is minimally absorbed by roots and slowly transpired through leaf surfaces. In large containers, there is considerable risk of plants rotting from excess soil moisture, and baby plants are particularly at risk in this respect. Small plants are thus most comfortable in small pots.

Soil Mix for starting Plants in Styrofoam Cups

A basic soil mix for growing seeds in small pots would consist of two parts top soil, one part peat moss and one part sand.  Or you can find custom made “seed starter” soil mixes at the nursery.
Each of these ingredients should be available by the bag at a well-stocked nursery or home-improvement center. To root cuttings from shrubs, ground covers, perennial herbs, succulents or indoor plants, utilize a mix consisting of one part sand and one part peat moss.

How to Plant Seeds and Cuttings in Styrofoam Cups

Flower or vegetable seeds should be lightly pressed into the soil mix or just sprinkled over the top and lightly covered with no more than 1/8 inch of the mix. Where cuttings are concerned, three should be inserted in triangular fashion around the center of each pot. In this way, when the cuttings root out, they will form a substantial, compact, highly visible plant that is ready to assume its own identity in a larger container or in the garden. The terminal 4 to 6 inches of a plant’s shoots referred to as shoot-tip cuttings generally make the best cuttings for propagation.

Rooting Fig, Pomegranate, and Rose Cuttings 

Deciduous plants should not be overlooked as subjects for propagation. Cuttings from leafless fig and pomegranate trees, for example, will root in the spring if they are taken at this time of year. When winter-pruning rose bushes, take shoot-tip cuttings and root them either outside in your garden soil, as long as it drains well, or in small pots.

Soil Moisture Concerns when Planting in Styrofoam Cups 

If you use Styrofoam cups as your propagation containers, punch a single hole with a pencil in the bottom of each cup for drainage.Check the soil daily for moisture. For seed germination you will want the soil to be constantly moist but not soggy. Where the rooting of cuttings is concerned, the moisture level of the soil can be allowed to fluctuate a bit.
Your greatest initial concern for seeds is that they might dry out before they can germinate. After germination, your concern is that you might overwater, causing the just-emerged seedlings to die from a fungal disease. With cuttings, the order of your concerns is reversed. Initially, you want to make sure you do not water so much that the stem of the cutting rots before roots can form. Later on, you want to make sure that the newly rooted plant gets enough water to keep on growing.

Planting Acorns in Styrofoam Cups

Tip of the week
Oak acorns are easy to germinate. Pick up unblemished acorns from the ground, place them in moist potting soil in Styrofoam cups, and they should sprout within several weeks. A more exotic way to germinate an acorn involves filling a wide-mouthed bottle one-third with water. Cover the opening of the bottle with a piece of cardboard. Attach a string with a tack or a staple to the cap of an acorn; suspend the acorn from the center of the cardboard. Attach the string to the cardboard so that the base of the acorn just touches the surface of the water. Within a few weeks, a root should emerge from the acorn into the water and, not too long after that, a shoot should start growing up toward the top of the bottle. Your oak seedling in a bottle makes an intriguing mantelpiece fixture.

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