We are now officially in spring. Last Saturday is known astronomically as the vernal equinox in our northern hemisphere.

This is when the sun crosses directly over the earth’s equator.

So now that we are in spring everyone is gearing up and calling in with spring lawn and garden questions, so let’s start with a few common calls this week.

Q: How do you transition house plants back outside?

A: If you hauled all your tender, outdoor plants indoors for the winter, now is a good time to start pruning, repotting and fertilizing these plants to bring them back out.

The main thing to check for is if the plants need repotting? A good clue is visible roots at the top of the pot or roots protruding from the drain hole. If you’re unsure, pop the root ball out of the pot and examine. If you see any roots winding around the root ball it is time to repot. When repotting use a pot at least twice the diameter of the old one.

Q: When should I fertilize my spring lawn?

A: This is a very common call every spring. I recommend you cut your lawn at least three times before fertilizing. Fertilizing now while weeds are still growing and the lawn is still dormant will only provide a booster shot for the winter weeds.

Proper fertilization is a key factor in keeping your lawn healthy and beautiful. However, you should always have a purpose for applying fertilizer whether it is to establish a new lawn, encourage growth from excessive wear or pest damage or simply to maintain color and health.

Q. What does slow release nitrogen mean?

A: Nitrogen fertilizer sources are classified as either “readily available” or “slow release.”

Products such as ammonium nitrate, urea and ammonium sulfate are very water-soluble and become available very quickly once applied to the soil. The advantages of such fertilizer sources are that they are generally less expensive per pound of actual nitrogen and plants respond very quickly following an application. Disadvantages are that they have greater burn potential, have a greater risk of leaching, and do not give extended results.

Slow-release formulations primarily contain nitrogen sources that are not immediately available to the turf. The oldest slow-release products are natural fertilizers such as compost and manures which release their nitrogen as the microorganisms in the soil break them down. Other sources combine urea with formaldehyde while many of the more modern products contain nitrogen forms that have thin plastic, sulfur, or resin coatings that allow water to dissolve them slowly. Osmocote is a good example of a slow release fertilizer.

David Carter is the director of the Adams County Extension Service. He can be reached at 601-445-8201.