I’m confused. Should I clear out my garden at the end of the season or not? I’ve been leaving my flowers’ seed heads for the birds and the dead stalks for pollinators and overwintering beneficial insects. Also, the structures look beautiful, especially in ice and snow! Recently I read that I should cut it all down and cover the soil with mulch to prevent erosion. Which is it?

Garden sanitation is handled differently between the two kinds of gardens: vegetable gardens and ornamental gardens. Because of myriad diseases and insect pests that can overwinter in vegetable garden debris to attack the next year’s crop, vegetable gardens should be thoroughly cleaned up. All above ground plant debris should be removed. Vegetable plants needn’t be pulled up necessarily, because this disturbs soil and brings up weed seeds. They can be cut off at the soil line. Their roots decompose and feed the soil. In ornamental beds, only remove diseased top foliage. The rest can remain to be enjoyed by man and beast.

I think I put too much lime on my lawn because it washed down the street! I added it because our soil is clay. Now what do I do? Will grass grow? It’s all mud now.

Lime doesn’t solve clay issues. Clay soil has tiny particles that are so close together that it can be very compacted and not let water and oxygen get down to plant roots. It may have plenty of nutrients. It is best improved by working in organic matter to make bigger spaces (pores) between soil particles.

Lime raises the pH of soil when soil is too acid. Plants grow best with a pH around 6.5 or 7, which is "neutral". (The pH scale runs from 0, highly acidic, to 14 which is highly alkaline.) When plants have a fairly neutral soil pH, they are able to use nutrients in the soil. When pH is too high or low, plants can't use nutrients, no matter how much fertilizer you add. To grow a good lawn, do a soil test. It will tell you how much lime to add, plus how much and what kind of fertilizer to add. Click on "Soil Testing" on the University of Maryland Extension’s Home and Garden Information Center website. A video shows how to collect a soil sample and a chart lists soil labs. You can plant your lawn when soil warms up in spring (though fall is the premier time to plant lawns). Until then, the bare soil should be covered with straw or mulch to prevent erosion that will carry away topsoil. Search ‘lawns’ on the website for how to grow a successful lawn.

University of Maryland Extension’s Home and Garden Information Center offers free gardening and pest information at extension.umd.edu/hgic. Click “Ask Maryland’s Gardening Experts” to send questions and photos.