Garden Doctors: The pluses of 'planting in hills'

Mira M. of Sebastopol asks: What does "planting in hills" mean?

I overheard a few people talking about doing this when planting his or her vegetable seeds and I didn't get a chance to ask them what that meant.

Planting "in hills" is a term used for the method of planting certain vegetable seeds in clusters. These clusters are not necessarily planted literally in raised mounds to form hills.

When they are planted in raised mounds, 4 to 6 inches high, the advantage is that the soil warms up faster and drains better, and water that collects around the base encourages roots to feed more deeply. Pumpkins, squashes, cucumbers and melons are the more common vegetables planted in hills, with 4-6 seeds per hill.

Once the seedlings are established, the hills are thinned so that only the sturdiest 2 to 3 seedlings remain.

Jessica C. of Windsor asks: I would like to start some vegetable seeds indoors, but don't have a place in the house where I could put the seed trays near a window. How could I start them outdoors and protect them from the cold weather and frost?

If you plan to start a number of seeds prior to transplanting them into the garden, there's nothing more satisfactory and helpful, short of a greenhouse, than what's called a cold frame.

You can buy one that's ready to assemble from a kit, or make your own from old storm windows and whatever lumber you happen to have around. Thick, clear plastic works well also, if you don't have access to glass windows.

They can be of any size to suit your needs and in the shape of a square or rectangle, where the sides are made out of wood, which will be the framework of the cold frame.

The top and perhaps the sides, depending on the height you make it, will be the windows or plastic.

Cold frames should be constructed so the top is on a slant to allow the southern exposure into the entire inside area. That means the back end of the cold frame is higher than the front. The window orientation should be slanted toward the south. The top piece is attached to the back end with hinges to allow you to open and close it.

A cold frame allows you to sow your seeds outside, eliminating clutter inside the house, and keeps the germinating seed and the seedlings growing even through a frost or two.

When the top is closed, the temperature inside is slightly warmer than the outside, which keeps the plants from freezing. It's a good idea to hang a thermometer inside to keep an eye on the temperature, to make sure it's warm enough for the specific vegetable seeds you want to grow.

If you hear that there's going to be a hard frost coming, throw an old heavy blanket or thick moving tarp over the top of the cold frame, to give them that extra bit of protection.

At the other extreme, when the sun gets hot, it can roast the plants, so keep the top open during the day. You can use a sturdy piece of wood to prop the top open. Remember to keep the plants watered! Keep the seedlings damp and not soaking wet or you could have a problem with diseases and root rot.

(Send your gardening questions to The Garden Doctors at pdgardendoctor@gmail.com. The Garden Doctors, gardening consultants Gwen Kilchherr and Dana Lozano, can answer questions only through their column, which appears twice a month in the newspaper and online at pressdemocrat.com.)