How to choose best container for starting seeds

Q. Should I start seeds in cells, flats or pots?

A. Each container has its advantages. However, your choice depends on what you are growing, and how you plan to transplant your seeds.

Flats or trays are shallow, rectangular pans with no dividing lines. Flats are only a good choice if you're planning to transplant the seedlings into the garden as clumps. You can scoop out a grouping of seedlings all at once and plant them in a large, wide hole together.

Cells are trays split into individual compartments. You can sow several seeds per cell, and then cut off the weakest seedling(s) leaving just one seedling growing in each cell. Each plant's root system develops within its own cell, making it easy to transplant them individually. Their roots do not become tangled like in a tray.

Pots have mostly the same advantages as cells. You can sow the seeds and trim the seedlings to end up with one plant per pot, each with a distinct root system.

Plastic pots or containers are preferable to clay pots when starting seeds, since they retain moisture more consistently. Recycled plastic containers, like empty yogurt tubs, also work well. However, make sure you have poked holes in the bottom for drainage. No matter what type of container you use, make sure it is clean. To sanitize a container, soak it in a 10 percent bleach solution (1 part bleach to nine parts water) for 15 minutes and let it air dry.

There is also a fourth choice for seed starting - biodegradable peat pellets. These are pellets that expand into a pot when soaked in water. The added advantage of these containers is that they can be planted in the ground with the seedling; there is no need to remove the seedling first, because the container ultimately breaks down on its own.

Q. We have a supply of wood ashes from our fireplace that we would like to incorporate into our garden soil. Is this OK to do?

A. Wood ashes from your fireplace or wood stove can be beneficial to soils in home gardens and plant beds, but they must be properly applied. Wood ash contains potassium, which can be a good natural fertilizer. However, depending on the specie of wood, wood ash can contain anywhere from 3 to 10 percent potassium; hardwood ash contains more potassium than those from softwood. When water comes in contact with the wood ashes, it forms potassium hydroxide. Potassium hydroxide is highly alkaline and can rapidly raise soil pH.

Before applying wood ashes, have your soil tested to determine your soil's pH. You should not apply wood ash if you have a high pH soil (>6.5).

When adding wood ashes, there are several guidelines you should follow:

• Never use ashes from treated wood.

• Always apply in thin layers to avoid ashes forming a hard crust.

• After applying wood ashes, do not apply any additional lime to the soil. Like wood ash, lime increases the pH of the soil.

• Apply ashes evenly and mix them into the soil. Don't leave ashes in lumps or piles on the soil surface.

• Do not let wood ashes come in contact with germinating seedlings or plant roots, which could result in root damage.

• If ashes settle on any foliage, thoroughly rinse plants after applying ashes. Ashes can cause burning of foliage.

• Don't use wood ashes around acid-loving plants such as azaleas, rhododendrons, and blueberries.

• Do not use charcoal grill ashes due to the chemicals used in the bonding process.

• Provided by Mary Boldan. Master Gardener Answer Desk, Friendship Park Conservatory, Des Plaines, open 9 a.m. to noon on Wednesday. Call (847) 298-3502 or email Cookcountymg.com@gmail.com.